Collections: Roman Roads

This week we’re taking a brief look at Roman roads because that was the topic which won out on the latest ACOUP Senate poll and on this blog we conform to the mos maiorum by following the Senatus Consultum.1 In particular the question here was from Matthew Runyon who asked, “What was so revolutionary about Roman roads and if they were so successful, why didn’t anyone else build them the same way?”

And I think those are both really fascinating questions, because Roman roads, in one sense, weren’t revolutionary. They were an old idea, but an old idea employed on a much larger scale and as is often the case differences in scale and implementation can become differences in kind. But those differences also go a long way to explaining why subsequent states in the region weren’t all rushing to set up their own, similar road networks.

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(Bibliography Note: There is a lot written on Roman roads so this bibliography will be far from comprehensive and I may end up missing some more recent works, since I don’t, myself, work on Roman roads. The classic reference is R. Chevallier, Les Voies romaines (1972), available in English in two translations, both entitled Roman Roads, one by N.H. Field and the other by A.L.F. Rivet; I cannot advise you on which translation is better. For the narrower topic of Roman roads in Italy, which also conveniently covers the origins and political motives of the system, the standard work is R. Laurence, The Roads of Roman Italy: Mobility and Cultural Change (1999). There is a very good, if quite short, introductory chapter on what we know about Roman roads and the state of the debate on them by Anne Kolb, “Via Ducta – Roman Road Building: An Introduction to its Significance, the Sources and the State of Research” in Roman Roads: New Evidence – New Perspectives, ed. A. Kolb (2019).2 On other comparable roadways, note R. Talbert, “Roads in the Roman World: Strategy for the Way Forward” in the same volume. Also useful for thinking about the place of the Roman road network in Roman understandings of space and empire is R. Talbert, Rome’s World: The Peutinger Map Reconsidered (2010). Finally, this being a topic in which there is a lot of classical geography, I would be remiss if I did not note that the Atlas of Classical History, eds. R. Talbert, L. Holman and B. Salway (2023). has gone into a second edition (in color, this time!) and is really handy.)

Imperial Roadways

The first thing worth clearing up about the Roman roads is that, contrary to a lot of popular belief, the Roman roads were not the first of their kind. And I mean that in a variety of ways: the construction of roadways with a solid, impermeable surface (that is, not just clearing and packing dirt) was not new with the Romans, but more importantly the concept of knitting together an empire with a system of roadways was not new.

The oldest road network that we have pretty good evidence for was the Persian Royal Road of the Achaemenids but these too were not the first (the Achaemenid dynasty ruling a vast empire from 559 to 330 BC; this is the Persian Empire of Xerxes and Darius III). Even before them the Assyrians (Middle and Neo-Assyrian Empires running from 1363 to 609 BC)3 had build roadways to hold together parts of their empire, though I confess I know very little of the extent of that road system except that we’re fairly sure it existed and like the later systems we’re going to talk about, it included not just the physical infrastructure of the roads but a sophisticated relay system to allow official messengers to move very rapidly over the network.

The modern perception of the Persian Royal Road is conditions perhaps a bit too much by Herodotus who described the royal road – singular – as a single highway running from Susa to Sardis. Susa was one of several Achaemenid royal capitals and it sat at the edge of the Iranian plateau where it meets the lowland valley of Mesopotamia, essentially sitting right on the edge where the Persian ‘heartland’ met the area of imperial conquests. Meanwhile, Sardis was the westernmost major Achaemenid administrative center, the regional capital, as it were, for Anatolia and the Aegean. So you can see the logic of that being an important route, but the road system was much larger. Indeed, here is a very rough sketch of how we might understand a whole system:

Original Map by the excellent Moss Maps, with a few modifications by me. The dashed line is the Royal Road as described by Herodotus (original to the map). The solid lines are the rest of the major trunk roads of the system as mapped in Henkelman and Jacobs (2021), drawn poorly by me. Please note their positions are not anything like exact and you should instead refer to Henkelman and Jacobs (2021) for a precise map.

Compare the dashed line – the Royal Road as described by Herodotus – with the solid lines, the rest of the system we can glean from other sources or from archaeology and you can see that Herodotus hasn’t given us the whole story. For what it is worth, I don’t think Herodotus here is trying to lie – he has just described the largest and most important trunk road that leads to his part of the world.

This system doubtlessly emerged over time. Substantial parts of the road network almost certainly predated the Achaemenids and at least some elements were in place under the first two Achaemenid Great Kings (Cyrus II, r. 559-530 and Cambyses II, r. 530-22) but it seems clear that it is the third Achaemenid ruler, Darius I (r. 522-486; this is the fellow who dispatched the expedition defeated at Marathon, but his reign was far more important than that – he is the great organizer of the Persian Empire) who was responsible for the organization, formalization and expansion of the system. And in practice we can split that system into two parts, the physical infrastructure of roads and then the relay system built atop that system.

In terms of the physical infrastructure, as far as I can tell, the quality of Persian Royal Roads varied a lot. In some areas where the terrain was difficult, we see sections of road cut into the rock or built via causeways over ravines. Some areas were paved, but most – even most of the ‘royal’ roads (as distinct from ancillary travel routes) were not.4 That said, maintenance seems to have been more regular on the royal roads, meaning they would be restored more rapidly after things like heavy rains that might wash an unpaved road out, making them more reliable transport routes for everyone. They also seem to have been quite a bit wider; Achaemenid armies could have long logistics tails and these roads had to accommodate those. Several excavated sections of royal roads are around 5m wide, but we ought to expect a lot of variation.

On top of the physical infrastructure, there was also a system of way-stations and stopover points along the road. These were not amenities for everyone but rather a system for moving state officials, messengers, soldiers, and property (like taxes). While anyone could, presumably, walk down the road, official travelers carried a sealed travel authorization issued by either a satrap (the Persian provincial governors) or the king himself. Such authorizations declared how many travelers there were, where they were going and what the way-stations, which stocked supplies, should give them. Of course that in turn meant that local satraps had to make sure that way-stations remained stocked up with food, fodder for animals, spare horses and so on. Fast messengers could also be sent who, with that same authorization, would change horses at each way-station, allowing them to move extremely fast over the system, with one estimate suggesting that a crucial message could make the trip from Sardis to Susa – a trip of approximately 2,500km (1,550 miles, give or take) in twelve days (by exchanging not only horses, but riders, as it moved).

All of which gives some pretty important clues to why royal roads were set up and maintained. Notice how the system specifically links together key administrative hubs, like the three main Achaemenid capitals (Susa, Ekbatana and Persepolis) and key administrative centers (Memphis, Sardis, Babylon, etc.) and that while anyone can use the roads, the roads serve as the basis for a system to handle the logistics of moving officials and state messages, which of course could also serve as the basis for moving armies. After all, you can send messengers down the royal roads, through the existing system set up for them, to instruct your satraps to gather local forces or more importantly to gather local food supplies and move them to the road in depots where the army can pick them up (and perhaps some local troops) as it moves through to a nearby trouble spot (while the nice, wide road allows you to bring lots of pack animals and carts with your army).

In short this is a large, expensive but effective system for managing the problem of distance in a large empire. Cutting down travel and message times reduces the independence of the satraps, allowing the Great King to keep an eye on them, while the roads provide the means to swiftly move armies from the core of the empire out to the periphery. We can actually see this play out with Alexander’s invasion. He crosses into Asia in 334 and defeats the local satrapal army at Granicus in 334. Moving into the Levant in 333, he’s met at Issus by Darius III with a massive army, collected from the central and western parts of the empire – which means that news of Alexander’s coming has reached Darius who has then marshaled all of those troops from his satrapies (and hired some mercenaries), presumably using his efficient message system to do it and then moved that force down the road system to meet Alexander. Alexander defeats that army, but is met by another huge army at Gaugamela in 331, this time gathered mostly from the eastern parts of the empire. While the Persian army fails in defeating Alexander, the exercise shows the power of the system in allowing the Great King, Darius III to coordinate the military efforts of an enormous empire.

So this is a system meant to enable the imperial center to control its periphery by enabling the court to keep tabs on the satraps, to get messages to and from them and move armies and officials (and taxes!) around. And doubtless it was also not lost on anyone that such a visible series of public works – even if the roads were not always paved and had to be repaired after heavy rains and such – was also an exercise in legitimacy building, both a visual demonstration of the Great King’s power and resources but also a display of his generosity and industry.

And I lead with all of that because the Roman road network works the same way, just on an even larger scale. Which isn’t to say the Romans were copying the Achaemenids (they don’t seem to have been) but rather that this is a common response to the problem of managing an uncommonly large empire.

All of which brings us to:

Roman Roads

The first thing to note is that when we talk of ‘Roman roads,’ we almost always mean the viae publicae, roads built by public officials (Initially censors who let out the contracts to build such public works, although later roadways get named after the consuls and praetors constructed them as the Romans build more of them) and was maintained by the state. But of course these major state highways existed within a wider network of local roads (a via vinciales or actus, pl. actuseverybody loves the Fourth Declension! It’s a step in the right direction) which might or might not be private (a privatum iter). That distinction is important, because it wasn’t that all Roman roads were of the high quality we tend to think of – the roads we’re thinking of were prestige projects undertaken by the state, but a whole less of private lanes and dirt paths existed too.

That said, for the major viae publicae, the combination of archaeologically preserved examples and a few references in literary sources gives us a good sense of what ‘best practices’ for Roman road construction were. To start with, obstructions were cleared and then a trench was dug where the road would go. The trench was then filled with three packed layers: a stone layer, then a gravel layer and finally a sand or cement layer. On this was placed the surface of stone blocks, cambered so that rainwater drained to the sides of the road. The stone surface was then held in place by an umbo (literally a ‘knob’ or ‘swelling,’ the same word is used for shield bosses) on the edges of the road. Within a town, the umbo might in turn border a stone sidewalk, but out in the countryside, that wasn’t present.

Via Wikimedia Commons, a diagram of the construction of an ideal Roman street, in this case one in a town (thus the presence of a sidewalk or semita on the sides).
Original Caption:
1 Native earth, levelled and, if necessary, rammed tight
2 Statumen: stones of a size to fill the hand
3 Audits: rubble or concrete of broken stones and lime
4 Nucleus: kernel or bedding of fine cement made of pounded potshards and lime
5 Dorsum or agger viae: the elliptical surface or crown of the road (media stratae eminentia) made of polygonal blocks of silex (basaltic lava) or rectangular blocks of saxum qitadratum (travertine, peperino, or other stone of the country). The upper surface was designed to cast off rain or water like the shell of a tortoise. The lower surfaces of the separate stones, here shown as flat, were sometimes cut to a point or edge in order to grasp the nucleus, or next layer, more firmly
6 Crepido, margo or semita: raised footway, or sidewalk, on each side of the via

On the one hand, we know that the high-quality construction of Roman paved roads impressed in the ancient world; Dionysius of Halicarnassus proclaims them one of Rome’s three most magnificent works (alongside aqueducts and sewers, Dion. Hal. Ant. Rom. 3.67.5; note also in this vein Strabo 5.3.8; Plin. HN 36.125). On the other hand, we also know that not all Roman roads were built to the same high standard. While we know that various Roman legislation spelled out required road widths, for instance, the actual width of Roman roads varied widely. And while we’re here, I should note, the story you have heard that modern roadway width or standard railway gauge being based on Roman road width (or, heaven help us, Roman ‘war chariots,’ a thing the Romans did not have) is rather wrong. Nor were they always well-constructed or maintained; Julian, for instance, bemoans a poorly maintained road in a letter to Libanius in 363.

Also, if I may stop a moment, one thing I hear frequently said about Roman roads is that their survival serves as some sort of indictment on modern road construction, “they don’t build them like they used to!” There are a few layered bad assumptions here. The first, of course, is survivorship bias; that road outside of Chalcis that Julian complained was sinking into a swamp probably isn’t available for us to see and similarly badly maintained or poorly constructed Roman roads are simply gone or only visible with archaeological methods and so unavailable for comparison. At the same time, modern roads are asked to do things which ancient roads were not; I do not suspect many Roman roads would last very long if hundreds of 20-ton (or more) trucks were rumbling over it daily. Indeed, preserved Roman roads outside of the cities often have deep ruts worn several inches deep in the stone from the passage of carts (carts and other vehicles were generally banned inside of Roman cities; city streets were for pedestrians). Finally we know that Roman roads, just like modern ones, required maintenance and reconstruction fairly regularly in the period of their use; Laurence (op. cit., 66) has a neat table of inscribed milestones on the Via Appia, for instance, referring to repair or reconstruction, with sections of the roadway repaired in stages from 97 to 110AD.

Via Wikipedia, a section of Roman road in Tarsus, Turkey, which shows some of the design elements, retaining a degree of its camber (note how the road is higher in the center and lower at the sides to allow water to run off) and the umbones that make up its curb.

Nevertheless, the generally high quality of Roman roads, as noted, was recognized in antiquity and is still apparent in their survival today. In contrast to many unpaved sections of Persian royal roads, for instance, Roman viae publicae were paved as a matter of course and standard widths (c. 3.5m wide; the oldest Roman laws, the Twelve Tables, set a minimum width on straights of c. 2.4m though as noted this was not always followed) were fairly generous. And they tended to be well-engineered, with relatively flat surfaces (which are often quite a bit less flat today due to ground shifting as well as the erosion of concrete between paving stones) and straight lines, though the notion that all Roman roads were ruler-straight is, of course, wrong (though some are!). In particular, the Roman system of road construction, while it demanded considerable up-front labor costs, was seemingly designed to keep long-term maintenance demands low. This was a style of road building which accepted big up-front costs in exchange for lower long-term maintenance, which of course demands a lot of initial state capacity to manage the costs and labor demands (something Rome’s successors would mostly lack).

So as roads go, the Roman ones were uncommonly good (albeit with a wider degree of variation than is often appreciated), but the marvel of the Roman roads is not that they had a few good, paved roads – states had been building paved roads for some time, as noted above – but that they had a massive system of them. Scale, more than quality, was the Roman achievement here, though the quality was also quite high.

The Roman Road System

The earliest roads of the Roman Republic were, of course, dirt roads; the first major paved Roman road to be built was the Via Appia, begun by Appius Claudius Caecus during his censorship (312-307BC). While the Via Appia would eventually become the road which connected Rome to Brundisium (modern Brindisi) – important for being the logical port to use when sailing eastward to Greece – the initial construction only went as far as Capua. The timing, coming during the Second Samnite War, was not an accident; the war was pulling central Italy, especially Campania (of which Capua was the chief city) into Rome’s political orbit. A road served to move Roman armies into the theater of conflict, but also to bind this new region more closely to Rome.

Via Wikipedia, a map of the via Appia. Note that the initial phase of construction only proceeded as far as Capua.

Roman road construction in Italy over the next several centuries follow this pattern (Laurence, op. cit., 14 has a handy map). The third century sees the addition of Roman roads cutting north into Etruria (the Via Aurelia (begun in 241) and the Via Clodia (paved in 225), to be joined by the paving of the Via Cassia, probably in the early second century), the Via Appia extended into Samnium (along with Roman power). The second century adds a ring road around Sicily (obtained in the First Punic War (264-241)), the Via Valeria (there are two roads by this name, I mean the one in Sicily) and the extension of the Via Appia all the way to Brundisium at last, coinciding with Rome’s building interests in the Eastern Mediterranean. At the same time, the second century also sees a marked expansion of Roman road networks in northern Italy into Cisalpine Gaul, as Rome secured and then re-secured these areas before and after the Second Punic War.

These early roads, particularly the initial construction on the Via Appia, would have represented really significant efforts by the Roman state and indeed Michael Crawford supposed that the construction of the Via Appia in particular motivated some of the earliest Roman coinage issues in order to pay for it (Crawford, RRC cat. no. 13/1). As Laurence notes, that means they weren’t just expressions of Rome’s expanding empire (at this point, just in Italy) but also a product of Roman politics. Appius Claudius seems to have gained a lot of clients in the process of building the road system and road construction was a big part of Gaius Gracchus’ political program in the late second century for the same reason (Plut. C. Gracc. 6.3). But they were also very direct expressions of Rome’s growing control of Italy, the construction of a physical geography which linked Rome key settlements in what was rapidly becoming Roman Italy; it is particularly striking how the earliest Roman roads form a hub-and-spoke network (with Rome at the center), but the wheel of roads that might connect one part of Italy with another come substantially later. The road system instead mirrors Rome’s relationship with the socii: just as the Roman ‘allies’ (really, subject communities in Italy) each in theory had a bilateral relationship with Rome (which left the smaller allied communities, in theory, atomized and thus much weaker in the relationship) so too they had a road to and from Rome, but not necessarily to and from the other regions of Italy.

At the same time, as Rome expanded its empire beyond Italy, the roads went with them. The first overseas Roman road was the via Egnatia, begun by Gnaeus Egnatius during his time as the proconsular governor of the province of Macedonia almost immediately after its annexation in 146 BC. The via Egnatia probably was a formalization and paving of pre-existing roads through the region, but it is also a good example of the shaping effect Roman roads could have on military affairs: it is not an accident that several of the key battles of the Roman Civil Wars are fought on or near the via Egnatia.5 Road construction in Gaul and Spain begins with the via Domitia, begun in 122 BC and named after Gnaeus Domitius Ahenobarbus (consul that year); the road ran from the Rhône through southern Gaul (Gallia Narbonensis, named after the garrison Ahenobarbus placed at Narbo, which flowers into a full Roman colony; this is modern Narbonne), crossing the Pyrenees and linking up to the northern part of a road system the Romans would build down the eastern coast of Spain.

Via Wikipedia, a map of the via Egnatia. If you are wondering why the road doesn’t cut south into Greece, of course later roads would do so, but Rome was slow to actually incorporate Greece directly as a province, opting instead to control affairs in Greece through Roman proconsular governors in Macedonia (who naturally had a strong hand in Greek politics, sitting as they were with a major army just to the north). Greece is formally absorbed as the province of Achaia in 27 BC, though by that point Rome had controlled affairs in mainland Greece for more than a century.

As we get into the Late Republic and especially into the Empire, it’s clear that road building has become a fairly standard element of military operations on Rome’s frontiers. Roman legions eventually came to contain specialist architecti who were specialists expected to be able to supervise a wide range of constructions, including planning out roads.6 Under Augustus, the Roman army becomes a permanent, professional standing force, meaning the legati Augusti who both governed Rome’s border provinces and commanded the armies there had access to the legion’s labor in peacetime.

At the same time, as Rome settled in to more fixed frontiers, the need for a more robust road network didn’t go away. Legions now shifting to defensive tasks needed the ability to shift along the frontier rapidly as needed, while road networks stretching into the interior where necessary for moving messages to and from the imperial center, which remained very much in Rome for the first two centuries of the imperial period. We see hints of how the military need shaped the resulting road network in its eventual layout. Edward Luttwak’s work on Roman strategy remains controversial, but one point I think he has right is that defensive concerns exerted some shaping force on roads close to the limes (Rome’s frontiers), with major roads often running parallel to Rome’s frontier (allowing forces to shift quickly to trouble-spots without opening lots of routes for enemies to penetrate deeply), while a smaller number of major trunk roads linked back to Rome (or at least to the Mediterranean, whereby one could sail there). This pattern is more clear, I should note, on the European limes than on the Eastern limes, but that’s to be expected as the character of Rome’s security challenges in those zones differed.

Like the Persian royal road, the Roman road system also hosted an official system of way-stations and messengers, strictly for official business. Scholarship tends to prefer the term vehiculatio for this system, though public-facing works often use the term cursus publicus for it. Official travelers received a permit (a diploma, a word generally used for state documents and permits) which would spell out their route and the provisions they were entitled to along the way. Part of the reason we know a lot about this system is that it was prone to abuse – officials and especially soldiers carrying a permit might have limited rights to requisition animals and vehicles from civilians as necessary as they went, with the assumption that the state would return or repay the cost of the seized property. In practice, it’s clear that system was open to abuse, with officials and soldiers requisitioning things they didn’t need or weren’t entitled to (they’re soldiers, so you’re not going to say no, because they’re armed) or which were used for private purpose (why not requisition some fellow’s cart and carry some trade goods if you’re making the trek anyway, right?). Imperial edicts cracking down on this sort of thing are a regular feature of the corpus of Roman official inscriptions. That kind of evidence is always hard to interpret: on the one hand it means cracking down on this kind of corrupt abuse was a meaningful priority for the emperors and their agents, but on the other hand it also means such abuses were never eradicated.

But the principle elements of the vehiculatio system were waystations, called mansiones and smaller stationes (relay-stations) which could provide rest-stops, fresh animals and food to official travelers. Those facilities were state run and for official business though; regular civilian travelers could not use them. We know that over time, traveler’s inns – cauponae or tabernae – sprung up along major roadways to meet the demand of travelers for rest and provisions, which of course had economic implications for the system’s greater usage (see impact below).

The scale of the resulting system was massive, with something on the order of 50,000 miles of paved roads stretching through every Roman province, with even more unpaved roads of one sort or another. As we’ll see in the next section on ‘impact’ this is where the scale of Roman roadbuilding produces an apparent difference in kind from earlier royal road systems.

Via Wikipedia, a map of the major arteries of the Roman road system. This is not all of the Roman roads, but covers most of the major trunk roads.

But we might well ask why Rome built so much more in the way of roadways than the empires that preceded and followed them. No source, to my knowledge, tells us, but I think we can see a few factors that could contribute. One obvious factor is the resources available to the Roman state were much more vast than any other Mediterranean state until the early modern period. By the time of Augustus, the Romans already controlled a population probably around twice that of the Achaemenids (c. 50m compared to c. 25m, very roughly) and governed an economy experiencing a marked expansion from those earlier centuries. And of course, the Romans were at it longer; the first major Roman road project, as noted starts in 241 BC; by the time that Nerva and Trajan are doing major repair works on the via Appia in 97-110, the Romans have been building roads for more than three centuries and are hardly done doing so. By contrast the Achaemenid Empire only existed for 229 years.

There’s also, I think, likely a military factor here as well: the Roman Empire due to its structure had more need of roads than the Achaemenids or other empires. For one, unlike many empires that deployed long-service local governors, Roman legati and especially senatorial governors typically had short stints – often as short as a single year – in their provinces before returning to Rome. Meanwhile, the main Roman center of governance was not mobile – the Senate did not meet anywhere but Rome and until the Crisis of the Third Century, most emperors tried to spend as much time in Rome as possible because it was the political center of the empire; one may not the contrast to the Achaemenid’s multiple regional capitals enabling the king and court to move if necessary. Finally, the structure of the Roman army and the way Roman frontier defense evolved also probably provided an impetus for more roadways. Once again, this gets into a contested topic around Roman strategy, but Rome tended to employ a large number of mid-sized field armies, stationed up and down the frontier, until the Crisis of the Third Century, rather than dispatching massive expeditionary forces from a handful of key administrative centers. That might mean that the number of places that needed to be connected to the system was greater and of course it didn’t hurt that all of those armies already had the ‘road-building habit’ as it were.

Finally, the roads themselves were also an important ideological component of the program of Roman power. The political impetus to roadbuilding in the Republic continued into the imperial period: just as road building could make Roman politicians in the Republic popular, they could aid the legitimacy of an emperor who benefited both from being able to grab (on coins and milestones) about roadwork but also who could perhaps count on some gratitude from workers employed on road projects in non-military regions. And the roads were also part of the visual pageantry of the empire. Richard Talbert, for instance, has suggested that the Peutinger Map – a large, somewhat geographically distorted map of the Roman road system during the Late Empire – might have been a copy of an original displayed in a place like the reception hall of Diocletian’s palace at Split.7 Consequently, Roman emperors had plenty of reason to lavish resources on the road network and to want to be seen to have done so – and as noted, they had plenty of resources to so devote.

Via Wikipedia, a snippet of the Peutinger Map, showing Egypt and Anatolia. As you can see, the map is distorted to allow it to fit in the space (yet is evidently produced based on a north-aligned original). The original map would have covered the entire Roman Empire, but in its current state at least one panel on the western edge is missing.


Impact is where we reach the point where the smaller ways the Roman road system is exceptional – unusually well-engineered, operating at an unusually large scale – come together to create a qualitative difference from the road systems which came before and after it. Again, it isn’t that Roman roads were the first state road system, or the first paved roads, or the first planned roads, or the first military roads, but this was the idea being deployed over a larger area, with far greater density of routes, constructed at a higher quality (and particularly for low maintenance).

Of course one immediate impact of the road network was the success of the Roman Empire. The Roman Empire was very large, but it was also built out on territory that spent the subsequent 1500 years proving that it was very hard, as a geographic matter, to hold together. The eastern parts of the Roman Empire seem to make a sort of natural unity and indeed states both before Rome (the Achaemenids and Neo-Assyrians) and after them (the Ottomans) manage to put together similar looking empires, but efforts to do the same in the west ran headlong into the difficult geographic and logistics of the task. Rome’s experience uniting Italy conditioned it to build the infrastructure that made holding western Europe, in particular, together and the Romans held it together for four centuries and change (longer in some places), in no small part because the road network enabled the quick and easy movement of officials, orders, armies and resources inland, away from the easier transport of the Mediterranean.

And of course that long Roman rule has massive downstream consequences, from the spread of Christianity to the emergence of the fourth, fifth, ninth and twenty-ninth most commonly spoken languages. Taken together, ‘bad, modern dialects of Latin,’ would be the second or third most spoken language!

Meanwhile it has generally been thought that the economic effects of the Roman road system were not only distinctly secondary but that the Romans – at least the elite Romans who built the roads – were probably broadly unaware or indifferent to them. Anne Kolb offers an effective rejoinder to this view in the opening paragraphs of her chapter (op. cit.) citing the example of Marcus Dunius Paternus, an elite of the coloniae Helvetiorum who financed the building of a substantial length of road on his own. As Kolb notes, he might have been motivated by more than just prestige or altruism – his own economic interests were heavily in timber and bulk architectural ceramics, both of which would benefit from a good roadway; it’s rare our limited sources let us see such obvious confluence of interests, but it probably happened pretty regularly.

In any case, the economic impacts do seem to have been significant. Movement through the empire, when it was not done by sea, rapidly became an exercise in following Roman roads, as the genre of itineraria – travel guides – attest. These guides listed cities in order which would be encountered on the road; so long as you followed the road, they might take much the place of maps (or even include a schematic map, perhaps a far less embellished and simple version of something like the Peutinger Map). Though we lack the evidence to quantify the impact of the road system on the economy, there’s little doubt that over time it because substantial.8

One of the reasons I think we can be sure about the economic impact is that we can see Roman roads reshaping settlement patterns in regions where they were new, even in cases where settlements were long established. J.B. Ward-Perkins, way back in 1962 did a study of the Roman road network in Etruria,9 noting that the Roman roads, built in the third and second century, reshaped settlement patterns. In particular, the via Flaminia, which cuts a straight(ish) shot through Etruria to give Roman armies a highway through the region to potential combat zones beyond, disregarded existing settlement patterns and thus doesn’t detour to hit major settlements or existing parts of the road network; the via Cassia was similar. And what we see is a movement of population away from older settlements now off of the major highways towards new settlement cropping up along them. It’s hardly the only settlement pattern change happening in this period in Etruria, but it is happening, which is really striking because urbanism in Etruria was quite old, with large, well-established Etruscan cities already existing in the seventh century.

As you might imagine then, the impact to settlement patterns in less urbanized provinces that then urbanized under Roman was even stronger. The originally Gallic settlement of Lutetia, for instance, sat on the juncture of the Seine and the via Agrippa along with several important local roads and as a result became a fairly major Roman regional center, growing in wealth and importance in parts because of its relationship to the road network. And if Lutetia doesn’t sound familiar, you may recognize it by its modern name: Paris. The fact that legionary bases (with the economic demand they created) and the road network coincided along much of the Roman Rhine-Danube frontier gave rise to new centers of urbanism; sometimes there was a previous smaller settlement present and sometimes not. Trier (Augusta Treverorum) and Mainz (Mogontiacum) are both classic examples where the confluence of Roman forts and roads produced cities that persist to the present. Even well within provinces one can see this; Lyon, the third largest city today in France, was Roman Lugdunum, a favorite of emperors because it sat almost precisely on the juncture of the different trunks of the via Agrippa and at the confluence of two rivers (the Rhône and Saône) making it an obvious administrative center in Gaul.

Meanwhile, the robust construction of many Roman roads has meant that they have lasted. Again, not all Roman roads were built to this standard, but many of the main trunk highways were and you can still walk parts of them today. Importantly, that meant they were still available to be used after the Roman Empire was gone and so in some places continued to exert their influence on settlement and economics patterns. The phrase ‘all roads lead to Rome‘ is not an ancient saying, but a medieval one (first used by Alain de Lille in the 12th century) because even then, the major old Roman roads did lead to Rome. That doesn’t mean every change in settlement pattern was durable; Ward-Perkins (op. cit.) notes that in Etruria, after the pax Romana ended, settlements moved away from the roads and back up to more secure hilltops. But especially in the European parts of the empire, where urbanism had largely begun under the Romans, those urban centers remained to be important cities in the Middle Ages and beyond.10

At the same time, I think it matters for the legacy of the Roman Empire in the West that its collapse does not lead to the rise of another empire of comparable size or wealth. The question, ‘why didn’t the fragmented successor states of Rome build large, interconnected road systems’ is largely self-answering: because they were fragmented, lacking both the resources and the vast expanses of territory to do that kind of infrastructure or to make it make sense to do so. Rome was unique in several ways: both in that its experience of conquest in Italy conditioned the Romans to build roads to enable military operations wherever they went, but also the Roman state just had a lot more state capacity than any of the states that followed it for a long time. Those successors (again, particularly in the western part of the Roman world) didn’t build vast road networks because they couldn’t. Though to be fair, even in the east where we do see empires rise that are comparable in scale to the Roman Empire, they’re not nearly so enthusiastic as the Romans about road building either. But of course that means the Roman road network isn’t fully replaced until the early modern period; in some places it really never was, with modern roads neatly following older Roman ones. That deepens the impact of the network both on the landscape but also on cultural memory.

So to conclude, in one sense the Roman road system wasn’t ‘revolutionary’ in that it wasn’t a totally new development or a clean, clear break with the past. In another sense, by taking an old idea – state (or ‘royal’) roads maintained by the state, with a system of way-stations for official business, but with the roadway itself open to the public – and employing it on a much larger scale and at a much higher quality of construction, the Romans really did do something new and in some parts of their empire, something unique in the pre-modern period.

  1. Translation: we conform to tradition by following the advice of the Senate.
  2. Note that this volume has chapters in German, French, English and Italian. Abstracts are translated but chapters are not, which may make this volume less useful to the non-specialist who may not read all of those languages.
  3. The Middle Assyrian Empire and the Neo-Assyrian or New Assyrian Empires were, in fact, the same state. We split them up because of a severe contraction in Assyrian power during the Late Bronze Age Collapse.
  4. On this, see Henkelman and Jacobs, 727-8
  5. The siege of Dyrrachium and the Battle of Philippi are both on the road directly, efforts to open or block the obvious route connecting the eastern part of the empire to Italy.
  6. You can get some sense of the staggering range of what an architectus might be expected to know from reading Vitruvius’ De architectura. Vitruvius’ work is almost certainly more broad-reaching than the typical architectus, but the range of structures and tasks is indicative of just how much engineering a legion could do (aqueducts, siege engines, major public buildings, drainage machines, surveying, heated bath constructions).
  7. This is not the only proposed use of the map, but I think it fits the odd factors about the map fairly well. On this, see R. Talbert, Rome’s World: The Peutinger Map Reconsidered (2010), 142-157.
  8. On this point, see Adams, op. cit. for discussion of the older view that road transport was prohibitively slow and expensive and newer arguments and evidence suggesting its valuable role in the economy.
  9. J.B. Ward-Perkins, “Etruscan Towns, Roman Roads and Medieval Villages: The Historical Geography of Southern Etruria” Geographic Journal 128.4 (1962): 389-404.
  10. I think part of the weight that Roman roads carry in the public imagination, I will say, has to do with the focus on the European parts of the Roman world. Roman settlement patterns in parts of the Middle East, for instance, are less durable, as Islamic garrison cities like Cairo and Baghdad compete with Roman era centers like Antioch or Damascus for precedence.

115 thoughts on “Collections: Roman Roads

  1. I’ve heard conflicting things about how Rome’s roads compared to those of the Han Dynasty in China. Any thoughts on this?

    1. Non-academic, but there’s some asides in here, including a bit about how differences in Chinese technology made them better able to cope with deteriorating roads than the west. httpss://

      1. I might suggest that the wheel barrow doesn’t reflect some technology that was useful but unknown outside of China, but a difference in the availability of fodder for draft animals. The rice farming parts of China is somewhat famous for it’s lack of ease in generating sufficient fodder for draft animals, but it’s remarkably high production in rice to feed human laborer. One wheeled carts do a good job making the most of human labor without animals, but are inefficient of human compared to ox carts or pack mule trains if animals are available.

        On the other hand, growing the fodder for draft animals seems to have been something of a feature of the wheat and barley crop rotation farming systems in Europe and Northern China. Those same donkeys, mules, and oxen would in turn allow for pack animals that would move far more freight per laborer than a one wheeled cart. Less impact on “human feed”, but more need for “oxen feed”. That availability of draft animals for carts and wagons might have driven the keeping of roads in northern China.

        It’s also important to note that a draft animal can be feed by grazing, and at the cost of travel time, can beat the “wagon equation”. A human can not, even when guiding a one wheeled cart.

        1. It was also bad for firewood, which is why Chinese food is traditionally chopped very small. Human labor for chopping was cheaper than firewood.

          1. Chopping firewood up increases its surface to volume ratio and makes it burn faster, not more completely.

            It occurs to me that rice-growing areas tend to be warm, and hence presumably had less need for firewood.

          2. I think they were referring to chopping up the food, e.g. stir fry, so that the food could be cooked with an absolute minimum of fuel. Ancient China was a living example of Malthusian limits, in which about the only good time to live was immediately after a large number of other people had died.

          3. smaller bits of food cooking faster, thus saving on fuel. make sense. the smaller bits of meat and veg would also make it easier to eat with rice and millet, the staples of the diets of the less wealthy populace.

          4. “I think they were referring to chopping up the food”

            Michael, you are right: I misread the comment. I think it is worth pointing out, though, that the “traditional Chinese meal” was rice, and the traditional European one was pottage.

        2. “a draft animal can be feed by grazing, and at the cost of travel time, can beat the “wagon equation””
          For non-priority “when it gets there” freight, sure. But in the context of armies hauling their supplies with them, all of those soldiers and followers need to eat every day whether they’re making progress or not. So for armies travel time as well as mileage is a vital concern.

          1. Agree on moving armies, both time and scale matter.

            Yet for the other 364 days or so of the year, the roads are moving freight to feed the empire, and in turn pay for those troops. Often literally with food in bulk. If your moving it by human powered cart, then each day’s journey is one more man’s food off the cart, nothing you can do. But with an ox wagon, each day’s journey is still the driver’s food off the cart, BUT if the oxen can graze, then that’s no where near as big a deal for an ox cart that’s much bigger than a wheelbarrow. Still a problem, but not as big a problem.

            Even still river and canals transport dominates over carts, and ocean transport over rivers, at least for bulk items like food.

          2. You can eliminate the need to transport the food of the man by using levied labour. You move the cart but the driver is a local who has a tax-like obligation to serve as a driver, bringing his own food.

            This is not theory. For example, until mid-19th century, the Finnish road network had legally required waystation inns, with the local farmers required to send a man, a wagon or sleigh and a horse to serve there, usually for a week at a time, once or twice a year. The postal service depended, similarly, on road-side farms that paid their taxes in kind by providing postal service: the mail carrier came (typically on foot) with the bag to a postal farm and gave it to the next man, returning home. The typical distance between two postal farms was ten or 20 kilometers.

            Of course, this is not free: the resources that are taxed in kind and used locally are still consumed and decrease the amout of resources that the state can extract, but they are, in a subsistence economy, often much more readily given than money.

        3. If you are moving armies around your own internal road network, you should be able to send messages ahead of the armies requiring grain etc to be stockpiled in advance of the army’s arrival. No wagon equation required.

        4. “It’s also important to note that a draft animal can be feed by grazing, and at the cost of travel time, can beat the “wagon equation””

          True but, at a guess based on being raised on a beef farm, you are probably going to need 5 or more grazing hours and that assumes good grazing. It works but it means a real reduction in travel time per day. Mongols could do that on the steppes but I am not sure how well it is going to work in more settled areas.

          There are likely other problem such as controlling wandering animals and possible predators.

          If you are willing to carry supplementary fodder then it would definitely improve the “wagon problem” but I doubt that grazing alone would solve it.

          1. If you are moving bulk goods, ox-wagons are fine. Slow (2 kms/hr), but a steady pull suited to bad roads, and a few hours grazing keeps them going. India and (until the 30s) Australia moved a lot of stuff this way. They did around 12-15 kms a day, which is not much less than troops marching a long distance.

      1. Requiring irrigation for the main crop meant that water control was vital, which probably made making canals effectively cheaper.

        1. There’s also just more river to work with – the Yangtze and Yellow rivers are both huge rivers fed by tons of tributaries, and depending on exactly how far the southern border of China reached at a particular moment the Mekong might also come up in relevance (albeit more in terms of trade routes and client states), which is also huge. Meanwhile the Nile is actually not particularly linked to much once you get past the headwaters in central Africa (the Congo is of course full of rivers), the Tigris and Euphrates are large but only intermittently under Roman influence, and the Volga is the largest river in Europe and kind of a joke on a global scale. Sea travel across the Mediterranean was of course continuously critical, but both the extent of the river network and the size of boats you could effectively use on it are substantially smaller within the Roman borders than the Chinese borders, pretty much regardless of where exactly those borders are at any given moment.

    2. I’m not too well-read on Han-era roadbuilding, but Brian Lander’s book “The King’s Harvest” discusses some of the major road works under the Qin. In the Warring States period, their seat of power originally lied on the western periphery of the Yellow River Valley (called the Guanzhong Basin), which was less fertile than the Central Plains region to the east. Because of that, they remained a second-tier power for centuries, until they managed to conquer the fertile plains of Shu (modern Sichuan) from native kingdoms to the southwest.

      This region is surrounded by steep mountains on all sides, so the Qin conquest (and the centuries of settlement and economic extraction that followed) relied heavily on a network of mountain roads built with heavy flagstones. Part of this network was built by the Shu Kingdom itself prior to the Qin conquest in the 4th century BCE; afterwards, the Qin expanded the road network to facilitate their control over the fertile region. The Shu Roads became something of a recurring motif in Chinese literature over the centuries (most famously in the works of 8th century poet Li Bai).

      Lander’s book talks at length about the state apparatus that the Qin state developed to meet this challenge. The anarchy of the Warring States period forced all the old feudal fiefs of the Zhou monarchy to play the game to harden themselves; most of them couldn’t keep up and were swallowed up in the intervening centuries. Qin’s survival was aided by its “backwater” location (which had the nifty bonus of facilitating the imports of horses and other livestock from neighbouring steppe peoples); the other major factor was a lack of rival nobility that could challenge the long-entrenched ruling dynasty, which allowed it to implement centralising policies without having them rolled back by aristocratic resistance (as happened to some rival states like Chu).

      By the time Qin Shi Huang declared himself emperor, the Qin state had developed an extremely robust administrative system to measure and extract the manpower it had (at least in its core territories; its attempt to expand this to millions of angry, newly-conquered subjects in the Central Plains would eventually bring its downfall). The first emperor ordered a slew of road networks built with flagstones and slate slabs: the most famous is the Straight Road running from Shaanxi to Inner Mongolia, but there are many other, smaller roads reaching well south of the Yellow River Valley (as well as three setpiece water works projects: the Zheng Guo and Lingqu Canals and the Dujiangyan irrigation system). Later authors (like Sima Qian in the Han Dynasty) would actually point to the sheer scale of these projects to illustrate Qin Shi Huang’s brutality and the callousness with which he treated the lives of his corvée labourers.

    3. Overall, Chinese empires tend to focus more on road-adjacent institutions (such as the systems of way-stations, state hotels, and messengers) than roads themselves. The only major road-building empire was Qin (221-207 BCE), afterwards most of the dynasties chose to construct canals instead, as water transport is much more cost-efficient.

      1. I suspect that rather depends on what you are trying to transport. Moving a cavalry regiment by water might not be so much easier than by road.

        1. That might be an explanation for why so many of the trunk roads in the map appear to run more or less along the shoreline, from port town to port town.

  2. A few follow up questions: I imagine that these sorts of roads required considerable labor to construct, even more than a few architects and a legion could easily provide. I’m guessing that the labor force mostly came from the local populace wherever the road went through, but how were those people recruited/kept on/paid/otherwise supplied? Or am I wrong and you had roving bands of road construction crews moving along leaving roadways in their wake?

    And as for leading to a rise in urbanism, especially in Europe, how did that work, demographically? My understanding is that ancient cities were demographic sinks which required almost constant replenishment from the countryside in order to maintain themselves. Did population density in those regions go up with Roman rule to provide a demographic cohort to now inhabit the cities? Or was the countryside ‘overpopulated’ to a degree that it formed a natural cohort that could do so? I suppose that’s possible given what you had in the farming series and how small farms tended to support more people than were usually necessary to run them, but if there was a long-standing demographic ‘surplus’, what was happening to those people before the Romans came along and created the conditions to send some of them to cities?

    1. To follow on with the question about labor force (an interesting question I’d also be interested in the answer to):

      How quickly could the Romans build roads? What’s the average amount of time to lay a mile of road through fairly level territory? Or is that something for which we have historical evidence?

    2. “A few follow up questions: I imagine that these sorts of roads required considerable labor to construct, even more than a few architects and a legion could easily provide.”

      I disagree. A legion was about 5,000-6,000 people plus auxiliaries. That’s a HUGE amount of labor, even assuming that only a portion of the paper strength was available for road construction (due to engaging in military activities, the legion being below compliment, etc). Chain gangs of prisoners did a lot of work in the past in the USA (now they typically work in agriculture) and I don’t think anyone would have put thousands of them together.

      To make a mile of road a day, a thousand people would each have to construct a bit over 5 feet of road. I don’t have a good sense of how deep Roman roads are, but I do know that someone skilled with a shovel (and it IS a skill) can dig a 6′ deep, 5′ long hole in less than an hour (I grew up in farm country and helped burry livestock that died from certain causes). Maybe another 45 minutes or so to tamp the ground (based on personal experience tamping an area that size, and I’m bad at it). It takes practically no time to spread the stone, though raking it even would take a bit (again, based on my experiences). Even if we assume each person was responsible for the whole 5′ long section of road, start to finish, it’s definitely within the realm of possible within a day.

      Some of these tasks would be much easier than others–tamping dirt is pretty much the opposite of fun, but laying gravel and sand goes really quickly and we can assume the soldiers would be well-versed in trenching (and I’d wager the officers used this as a training exercise–trenches are useful in war, and you’ve got a perfect opportunity to teach the new kids how to do it). If you assign parties for each specific task you get efficiencies due to the way humans work (even if you dig today and spread sand tomorrow, you’re going to be more efficient than if you try to do it all in one day), so actual production rates could be significantly higher if you allocate labor properly.

      I’ve done enough construction management to be curious as to how that would work in practice….Get a few thousand people together and use Roman methods to build a Roman road, to see which methods work best….It would be…well, not fun, this sort of labor-intensive activity is brutal no matter who you are, but it would be interesting.

      That’s assuming materials were available of course. THAT’S where the labor is going to be. Suitable stone, sand, and the rest simply aren’t uniformly available. You’re going to have to mine the stuff and haul that stuff around. You may have to process it–well-graded and poorly-graded course sand are different; 57 stone is different from crusher run; both in ways that matter for road construction, meaning that sometimes you want one and sometimes you want the other and thus both need to be available. Someone’s got to cut the stone to size. And that part probably isn’t going to fall on the legions. There aren’t enough of them to do it, and it’s not activities within their wheelhouse. Of course, conveniently by definition if you’re building a road, you’ve got a road for that stuff to travel on!

      1. My great-grandfather, according to family legend, dropped out of middle school to become a ditch-digger. He was terrible at it, in spite of being a strapping young lad, and only made it through because he was also quite personable and the broke-down alcoholics on either side of him liked him enough to finish their trench sections and then clean up the last third of his.

        Using a shovel, especially for digging holes to spec, is absolutely a skill. (If you just want to fill a wheelbarrow with some dirt, somewhat less so in my experience. But maybe I just haven’t seen a professional do that.)

      2. AFAIK a roman legion with auxiliaries had about 10.000 men and the legions had their own stone quarries

      3. You are assuming all the materials are just there, waiting to be used. I would suspect most of the work would be in getting the stone to the place. Stone is not freely available everywhere, sometimes it would have to be transported a long way. And someone has to first cut it from somewhere. And a lot of skilled work to cut the stone for the final layer. And then a lot depends on terrain, if it’s rocky, good luck digging the trench. If it’s swampy, you need to drain it first. If there are rivers or streams you need to build bridges. If it’s a forest, you need to cut down the trees and remove the trunks. All in all, it’s a lot of work. But then they had a lot of time to do it too, and I agree, a legion of people is a big workforce.

        1. “You are assuming all the materials are just there, waiting to be used.”

          Well, yeah. I said that, in my last paragraph, along with a brief description of the sort of thinking involved with procurement and transportation that this would cause. Given the presence of various types of rock from various parts of the Empire in Rome, we can assume that Romans were aware of these issues and could handle them well enough.

          And I agree that there’d be a lot of variation. Terrain is going to be an issue. For that matter, wars are going to be an issue–you can’t build roads if you’re in the middle of combat. I was thinking in terms of a standard, typical construction project; a competent construction manager in any day could easily take this and adjust it for local conditions. And I’d imagine bridges would be somewhat specialized, due to higher risk. Building a road can be done with grunt labor if you have sufficient command and control (and the Roman legions did). Same with draining swamps or busting out rock. Bridges, on the other hand, are fairly complex, even simple ones. They are also militarily important and expensive. All of that means you really want someone who knows what they’re doing!

      4. given that a Roman legion could dig the defensive trenchworks for a marching camp in an afternoon, and did so pretty much every day, i’d imagine they were pretty good at digging and construction. (a roman marching camp was surrounded by a ditch 5ft deep and 3ft wide, on average, with the excavated earth used to create a berm on the inside edge of the ditch, which would be fitted with a wall of spikes for additional defense. the camps measured about half a mile per side in a square. it’s been estimated that a 2100 man legion could erect such a camp with about 5,600 man hours of work.. so an entire legion working on digging would take about three hours, while if they had only half digging and the rest on guard you’d be looking at 6 hours.

        i have no doubt that the slow part of making a roman road would have been the shipment of stone and gravel. and it is worth noting that usually installation of roads came well after the region was nominally pacified. it wasn’t something you did while on the march in hostile territory.

    3. Draining off people to the city, particularly from the farther-off regions, meant that more people survived in the country, because the food had to be shared with fewer people. Like the rebound effect after a disaster.

      1. That doesn’t work unless the overall population is lower, the food the city eats comes from somewhere.

        1. That’s why the distant regions, where the food can’t come from, are important.

          1. The grain that the inhabitants of the city of Roman ate came from North Africa during the Imperial period, their olive oil, if Monte Testaccio is any indication, largely from Hispania Baetica. Neither location is particularly close to Rome.

    4. but if there was a long-standing demographic ‘surplus’, what was happening to those people before the Romans came along and created the conditions to send some of them to cities?

      I suppose they died in wars (well, the men at least). Before the Romans come along, you have a lot of communities constantly fighting against each other. And that’s what the Romans do with their demographic ‘surplus’ as well for the first few centuries. When Roman military mortality drops in the second century BCE the Republic falls into crisis.

  3. I suppose the most obvious empire to compare with Rome, in terms of size, longevity and state capacity, would be China. So I find myself wondering how the Chinese state road network compared to that of Rome.

    1. Well China had it much easier than Rome in a lot of ways, so it isn’t clear the road networks would be very comparable. Maurya might be an interesting comparison in both cases, though.

      1. Imperial China had a long history of both public roads, and also an Imperial courier system similar to the Cursus publicus of Rome. This system also made use of the canal and river transport system where appropriate – the Grand Canal is 1776 km long, and was largely completed in the Sui dynasty (581–618 AD), and there were a number of other canals. So, I think roughly, that over time for North-South communications long highways came to be less necessary, while they were still used a lot for communications with border regions in the West.

        While Sima Qian, in the “Records of the Grand Historian,” describes the building of the The “Qin Zhi Dao” (Qin Direct Path), a 750 km road build in the first, Qin, Dynasty, I think the description of the courier system in “Treason by the Book,” about the last, Qing, Dynasty, might be more approachable. The courier system almost seems like a character in this history by Jonathan Spence, with the Emperor and his officials continually sending notes, memos, presents (Hami Melons from the Emperor!), prisoners and, of course, the book (Awakening from Delusion) itself, all at speed over the courier system.

    2. The usual example (for a very different kind of terrain, and only a tenth the length) is the Incan royal roads: Built through some truly nightmarish terrain and quite impressive (though using very different construction techniques)

  4. “The modern perception of the Persian Royal Road is conditions” -conditioned

  5. While reading this I couldn’t help but think of parallels to the Interstate Highway system in America. That’s another large road-building project, initiated (or at least justified) initially as a military project, that has had substantial economic impact. And, of course, also put together at a time of high state capacity.

    And the story of the roads pulling affecting settlement patterns makes me think of the movie Cars (of all things), and how the locals complain that the Interstate destroyed their small town; that’s not an uncommon consequence of the Interstate system.

    1. The Autobahn was similar in this respect. It could move troops much more flexibly than the railway system.

      1. Maybe it seems that way, but in World War II the Germans relied on the railroads whenever they could, and from everything I have read, the autobahns played a negligible role in German military logistics.

        1. Eisenhower was impressed by the German autobahn system, which I’ve heard lead him to championing the US interstate system.

        2. Wasn’t access to oil, or being able to make it from coal, a bottleneck for WWII Germany? Makes sense to use the far more efficient rail system…

          1. There’s also the point that highway systems don’t help military mobility much when said military mobility is by horse: the German armed forces in WW2 were way less mechanised than we imagine from our exposure to Allied media. (I’ve seen a number of 18% of divisions fully mechanized in 1941 but I’ve no citation for that, so please add salt. :-))

          2. The Germans were well aware of the supreme advantages of mechanized transport. They were also well aware of the critical shortages of not only petroleum but rubber. The latter especially had to be reserved for military uses for which there were absolutely no substitutes (and they tried such things as Buna-N in an attempt to).

    2. We tend not to remember now, but the better modern equivalent might be railroads, which certainly established patterns of settlement across the Western US and Canada. Even in more local regions such as Southern California the location of towns and the direction of development followed the steam and interurban electric railroads. In the 1950s all of LA’s original freeways duplicated interurban routes. In a number of places across the Midwest some towns moved lock, stock and barrel to the nearest railroad, just like moving near the road in Etruria.

        1. On the other hand homesteaders trying to raise a crop on western land with undependable rainfall (encouraged to so that the railroads would have customers), in an era when mechanization was leading to fewer individual farmers with every passing decade, set the stage for the brutal contraction of the farming industry in the 1920s and 1930s.

    1. Yes, somehow when you get a notice from the Parking Violations Bureau it never says “your tax dollars at work.”

  6. “one may not the contrast to the Achaemenid’s multiple regional capitals”

    not -> note

    “an emperor who benefited both from being able to grab (on coins and milestones) about roadwork”

    Less certain of this but I think “grab” should be “gab”.

    1. was maintained by the state → were maintained by the state
      a whole less → a whole lot
      Rome’s building interests → Rome’s budding interest
      linked Rome key settlements → linked Rome’s key settlements
      where necessary for → were necessary for
      the Achaemenid’s multiple regional capitals → the Achaemenids’ multiple regional capitals
      difficult geographic and logistics → difficult geography and logistics
      holding western Europe, in particular, together → holding western Europe, in particular, together possible,
      urbanized under Roman → urbanized under Roman rule

  7. Bret, as a classicist, what opinion do you have of Moreno Gallo’s work? ( for some publications) Most of it is unfortunately in Spanish so there may be some language barriers here.

    He has been very influential in rising awareness about roman roads in Spain. There is also some science/humanities division here. He was initially an engineer and his publications typically have technical approach (e.g. how does roman water works coincide or differ with modern approaches? Would that reconstruction need to cope with sedimentation or erosion and if so, how did they solve the issue? Can we reconstruct the construction/topographical procedures from roads considering the existing remains? Would this dam have been enough to supply water for this much irrigation in roman times? etc.)

    He got a lot of media diffusion recently and his work seems solid from a technical point of view. I’m an engineer myself and for example his aqueduct analysis seems sound (current channels and roman channels are constrains by the same physics and got pretty similar designs). However, with that background/focus I guess he is a bit of an outsider in traditional classical circles (I think he got a History degree too, but I’m not familiar with his biographical details). Most of the articles in the link above, for example, are published in engineering journals rather than a typical humanities-oriented journal. I think this and the language issue may mean his work has been more restricted to some circles.

    I remembered him because he is an outspoken critic of the typical roman road cross section you showed in the article. He has repeatedly insisted these reconstruction are a didactic problem since many roman road would be different in the outside because the stone layer may not always be needed (depends a lot on traffic and soil conditions, that cross section is most likely typical for a periurban area whilst rural roads or sections between cities may be different). Thus, there were roman roads with a different aspect than most people expect, and stone-face roads that are not roman. He has managed to trigger some debate in Spain about roman road preservation (or lack of, to be precised) as well as some dubious reconstructions/interpretations by authorities aiming to bring tourism but I never read a classicist view on his work.

    1. ..and one of those roads (the Fosseway) passes within a few hundred yards of where I am sitting. We have some good roman remains in Bath as well.

    2. Hey, I thought about the same guy when I saw the article. Actually the video about road building is translated to English too!

      I love how some of the roads fossilized until the modern times. N-340, for a long time the longest road in Spain, followed the Via Augusta in a lot of parts.
      Or near when I grew up, in Barcelona, the narrow streets Carrer d’en Blanco and Carrer de les Ànimes correspond to a very old (allegedly) Roman secondary road. The curious stuff is that the parcel divisions in the block that separates those streets fossilized the shape of the road, so today there’s a building out there whose walls don’t make 90° angles because an engineer 2000 years ago decided it was the most comfortable place to go through (Rambla Brasil 14)

    3. What you say is a good explanation of Moreno Gallo’s approach. I immediately thought of the works of this man. If I may I would say it in my words 😉

      Isaac Moreno Gallo is an engineer that studied History when he retired. He has a number of publications in Spanish about roads and a YouTube channel. He has a very technical approach and he has a different and challenging view on the traditional image of Roman roads. He claims they weren’t paved, but the archetypical examples we always get are those of (peri)urban areas where it would be more of a street (strata) than road. They were instead gravel packed (excuse me if I have some terms wrong, non-specialist here) and wouldn’t have those stones on the surface. The thing that he points to as the most interesting aspect of Roman roads, from an archaeological expertise, is the difference with Andalusian (Muslim Spain) roads, or any other kind till nowadays. The evidence relies on: width, side barriers and preparation to evacuate rainwater, the layers, and most importantly, the measurement (done by agrimensores) of the heights and orographics of the terrain, that allows the roads to go through the most plain way, avoiding slopes, as happened with aqueducts, but not in the same way, of course.

      Cheers tocayo!

  8. I’m a rank amateur when it comes to history, but something I’ve noticed is that the Romans are pretty consistently credited with construction projects — fortified camps every night on the march (with the “engineer corp” being the prestige branch of the military), the road network, monumental architecture, a deep and abiding love for plumbing/waterworks (I’d love to see a post about Roman plumbing)… The impression that I’ve gotten is that the one thing that Romans love almost as much as winning wars is building stuff.

    Am I just seeing things (because that kind of stuff is normal for a state with that much state capacity), or was this an actual cultural quirk that the Romans had? If so, do we have any evidence for why they were so construction-happy?

    1. It occurs to me to wonder whether a Greek hoplite would be so willing to do heavy labor.

      Also that any roads built by legions before Marius were being built by Rome’s middle class — the men wealthy enough (themselves or their fathers, I guess) to afford a mail tunic, not to mention helmet, shield, and weapons.

      1. Pre-Marian the Roman middle class consisted of yeoman farmers who were doubtless no strangers to manual labor. If they were wealthy enough to have slaves do all the work they were either patricians or nouveau riche.

    2. My guess there are several reasons :
      – Legion is paid professional army, which provide vast trained labour (contrasting with soldier-farmer of Later Empire or Chinese)
      – Roman build in stone which survive (unlike Chinese)
      – Roman had larger army (compared to cavalry-based Empire)
      – Roman had larger state capacity (compared to feudal/semi feudal nature of other Empires)

  9. >The political impetus to roadbuilding in the Republic continued into the imperial period: just as road building could make Roman politicians in the Republic popular, they could aid the legitimacy of an emperor who benefited both from being able to grab (on coins and milestones) about roadwork

    I am reminded of how many runestones in viking-era scandinavia specifically commemorate the building of bridges (usually with a note about the bridge being raised in the honour of so-and-so local potentate)

    Also, should probably be “brag” rather than “grab”

  10. One thing I’ve seen argued is that the roman road system was mostly different in precisely that they paid the up-front cost and reaped the benefits of relatively durable, easy to maintain roads: There are examples of even smaller socities or non- or proto-states building fairly extensive road systems (there is a road system of sorts through germania, possibly built as an extension of the roman one by local rulers) but since those lack the resources of the roman state they often build “on the cheap” (the exmaples I’ve heard talked about were “paved” with wood for difficult sections) which then requires a ton more maintainance and so fall into disrepair pretty quickly and requires constant upkeep which these states are either incapable of or only capable of for short periods of time, and then afll into disrepair.

    And this to some extent follows the extensiveness of the roman road network too: Since the romans spent the time building the network well, they had to spend less time and effort maintaining it, which meant they could build *more* roads.

  11. [T]hat road outside of Chalcis that Julian complained was sinking into a swamp probably isn’t available for us to see…

    “When I first came here, this was all swamp. Everyone said I was daft to build a road on a swamp, but I built in all the same, just to show them. It sank into the swamp. So I built a second one. That sank into the swamp. So I built a third. That burned down, collapsed, then sank into the swamp. But the fourth one stayed up. And that’s what you’re going to get, lad: The strongest road in all the Empire.”
    Emperor Julian, probably

  12. For those of us who live in the modern world, seeing a “road” with an elevated “sidewalk” on each side of it is not unusual – the sidewalk is for pedestrians, and the road is for vehicles, it being rather dangerous for pedestrians to occupy the same space as high-speed automobiles.

    But is that how these ancient roads were actually used, considering they didn’t have high-speed automobiles? Were the centers of roads in the cities occupied mostly by oxen-hauled carts, while foot traffic huddled on the elevated sidewalks?

    Or if not, what was the purpose of the elevated sidewalk? To keep water runoff from the road confined to the gutters and away from the adjacent buildings?

    1. My understanding is that in cities the roads would accumulate lots of general dirt so they weren’t the nicest places to walk even if the camber meant that most of it ended up in the gutters and they were clear enough not to impede traffic. Elevated sidewalks would stay cleaner and you can keep them clean easily by just sweeping stuff into the roadway. Pompeii’s streets even have a bunch of regular stepping stone ‘crosswalks’ so you can cross while remaining at sidewalk level (although they’re much rarer at other sites, so maybe Pompeii was exceptionally dirty). See here:

    2. Having spent a little time walking in the third world, I suspect it was to give pedestrians a a way to avoid the dung of transport animals. Particularly after a rain, I suspect the streets were much of the time a dirty mess.

          1. I might not have much chance to, if the neighbouring farmers dislike leaving something valuable and useful in the middle of the street. Farmers used to pay good money for dung.

    3. In addition to other suggestions, I would guess that holding the road in place was a partial function. If you just lay pavers, even on a good base, then walk several thousand people across them, they’ll shift pretty far, potentially enough to make the road hazardous to traverse. By putting the pavers in a bit below grade, and having elevated blocks beside them to confine them, you prevent that. The pressure from the soil around the road will act to hold the pavers in place.

      The hard stone is necessary because soil will tend to flow over time–it’ll get washed out by rain, stepped on by animals and people, plants will grow in it, etc. The pavers would prevent a lot of that, at least on the timescales of a few centuries. (Granite will eventually break down into clay and sand, but it takes a long time. Limestone wears away faster, but still slow enough that you can keep ahead of the maintenance.)

  13. Interesting as always.


    is conditions perhaps

    although later roadways get named after the consuls and praetors [who] constructed them as the Romans build more of them

    a whole less of private lanes and dirt paths existed — mess? lot?

    road diagram caption is missing ‘7’

    while road networks stretching into the interior where necessary for moving messages — something is off here

    both from being able to grab — gab?

    build the infrastructure that made holding western Europe, in particular, together — missing a ‘possible’

  14. Similarities to the US interstate highway system are (if you’ll pardon the phrase) “legion.” Both systems were motivated by a perceived need to speed troop movements and in both cases, the routes taken had the effect of diminishing cities bypassed and boosting the growth of cities (new or established) favored by access to the new roads.

  15. I suspect the roads also played a big role in why the Romans were essentially the Borg in terms of assimilation. They increase long-distance mobility and when a Celt and Numidian run into each other they are going to speak in Latin (for that matter a Celt and a Celtiberian might well for all I know, guessing they were far enough apart mutual intelligibility was challenging?). Interestingly the Inca had a good bit of success with assimilation considering they lasted less than 100 years and I suspect them also being grand roadbuilders played a role.

  16. Bret, as I read the post on Saturday morning (morning in PDT) the following problems still appeared:
    had build roadways to hold together > built
    perception of the Persian Royal Road is conditions > [meaning unclear?]
    but a whole less of private lanes > [Is the word less intended to be mess?]
    interior where necessary > were
    sprung up along > sprang
    one may not the contrast > note
    being able to grab . . . about roadwork > [meaning unclear?]
    the difficult geographic and logistics > geography [or missing word: “geographic distances”? Or other?]
    urbanized under Roman was even stronger > [missing word: rule? or influence?]
    importance in parts because of > part

  17. The archetypical Roman road is clearly engineered for marching troops – fairly narrow, hard-paved, steep gradients. Did it have something better suited to carts or horses alongside?

  18. The citation to Jacobs and Rollinger’s “Companion to the Achaemenid Persian Empire” seems to be missing. Not sure where that estimate of the population of the Achaemenid empire as “25m” comes from, McEvedy and Jones give ~17 million in 400 BCE (danger danger!) and Aperghis guessed 30 to 35 million in 350 BCE.

  19. “The siege of Dyrrachium and the Battle of Philippi are both on the road directly, efforts to open or block the obvious route connecting the eastern part of the empire to Italy.”

    In a similar fashion the 1st and Second Battles of Bedriacum, that decided the Year of the Four Emperors, were fought at what was effectively the junction of the Via Postumia, Via Amelia and the road from the Great St Bernard Pass.

    1. Possibly part of the Roman emphasis on minimizing maintenance: yes it’s laborious to up front cut through hills, fill in swamps, etc. But once you have, you’ve minimized how many mille passuum you have to upkeep.

      1. So why has no-one else adopted this ruinous policy, not least on legionnaire’s legs having to walk uphill and down dale just to save half a mile? Every been on a straight piece of modern motorway? Don’t we want to save on maintenance too? This is a vital question that needs answering to understand the origin of Roman roads.

        1. I think it probably also has something to do with Roman values. The Romans liked to see themselves as imposing order on a disordered space and they liked grid plans for both fields and towns (though ironically Rome itself was an unplanned city with an irregular street grid. Roman *colonies* however, were planned with rectangular street grids).

          A straight road cutting through rough country is – like Roman camps that, as Polybius notes, almost spitefully refuse to conform to local terrain – a powerful statement of a willingness to enforce order on the land rather than the other way around. The Romans were like that.

          1. What do you mean ‘also’? Using grid layouts for new towns is nothing special. Being spiteful to local terrain and enforcing order on the land by employing daft civil engineering principles is. On account of it being plain daft. The Romans were most definitely not like that. They were quite sensible.

          2. Sputnik had no scientific, economic or military value by itself. But it showed to those who have eyes to see that the USSR could also put, say, nukes anywhere on Earth, in a manner that was not subject to interception by aircraft or then-existing missiles.

            In the same way, “purposeless” but technically impressive earthworks show to those who have eyes to see that Rome can win sieges as a matter of routine.

          3. “Sputnik had no scientific, economic or military value by itself”

            Sputnik-1 certainly had scientific value. It was spherical so that it could be used to track atmospheric drag at its orbital altitude (which was totally unknown at the time) and, also, its timing signal initiated the the era of radio tracking of satellites.

            Also, all satellite navigation, including the GPS used by your cell phone, derives directly from the radio pulse signal broadcast by Sputnik 1. In the US, satellite navigation started from radio observations of Sputnik 1 from the roof of Johns Hopkins APL south of Baltimore – see

          4. Sputnik had no scientific, economic or military value by itself

            The early satellites confirmed the performance and especially the guidance systems of the rockets that launched them. And simply timing them as they orbited the earth contributed to geodesy- the mapping of subtle variations in the Earth’s gravitational field, which directly impacted ICBM accuracy which was of crucial military importance.

    2. They are not straight, but they do tend to take shorter steeper paths than modern roads. This is because they are primarily for foot traffic, and it is less tiring to go over a hill than take a longer route around it (you see this in places where foot traffic is the norm, like the path network in the Himalayas). I suspect the wagons and pack horses took a longer route of beaten earth (stone is hard on hooves, especially before horse-shoes), which has not lasted or been covered by newer roads.

      1. No, they are dead straight, geometrically straight, leastways they are for long stretches in Britain. If you think it is less tiring going up than going round, you should try it sometime. As for wagons preferring disappearing paths than smooth roads, well again you should try it sometime. Turning to horses, Roman roads were built for horses! With changes of horses at regular intervals since they were primarily for speed of communication.
        I will however grant that packhorses used traditional droving routes.

        1. I have tried it – I spent a lot of time in the Himalayas. Roman roads in, say, the Appennines, typically have much shorter, steeper gradients (not dead straight!) than the modern road. Stone is easier on the wheels but hard on the hooves, and steep descents are tricky for animal-drawn vehicles (more so as Roman carts do not seem to have had brakes – so they would need to lash the wheels or use a drag-log).

          de Camp (Ancient Engineers) notes that Roman road-builders often provided an unpaved strip along side the paved.

      2. If the roads were primarily for moving _armies_, I can see wanting as short a road as you can get away with. Minimum distance = minimum time = both fastest response to military needs _and_ less food you have to acquire to feed the armies. Whether you accept putting a road on the hill or doing the work to remove part of the hill.

        If the Romans really did have straighter roads than others, and kept doing so, it seems rather arrogant to assume they were daft.

    3. The ideal road might not be perfectly straight, but it does not follow that a randomly picked curve will be more ideal than a straight line. If Roman roads were straighter than most, that suggests they were more likely to build a road from scratch, and less likely to just improve pre-existing local roads.

      Manhattans streets are straighter than those of Central London; it does not follow that they were worse laid out than those of London.

  20. How does one click the Like star on comments? It apparently requires a WordPress account- but those accounts seem to be for original authors, not readers commenting on blog posts. I’m confused.

    1. If you are signed in to this blog series, you ought to be able to click it just by using your cursor.

        1. Are you using Safari? On my Mac I have to use Google Chrome to log in, the Safari login never works

    2. I have a WordPress account but have never published anything. It lets me make comments and like other’s comments. (There may be other ways to comment, I don’t know. There’s a button suggesting Facebook accounts might work too.)

  21. Censor Appius Claudius Caecus was a contemporary of Diadochi. Who were ALSO new-broom rulers trying to leave their mark on a previously settled but barbarian landscape.
    Alexandria, Antioch, Seleucia, Pergamon were centres on either new sites or previously unimportant. Apart from building the cities themselves, did any of the diadochi build roads? How was Royal Road run under Seleucids? Note that Susa was still under Seleucid rule but the old route did not go to Antioch on the Orontes. Or Egypt… the Persian road is shown ending in Memphis, no road to border on Syene, and no road to Alexandria either. Did Ptolemies do anything about it?

    1. Can’t comment on the details of that map (which is a very coarse simplified large-scale map!) but before the Aswan Dam the easiest way to move along the Nile was by boat. The wind usually blows upstream so raise your sails to go upstream and lower them to go downstream. Herodotus already commented how much the black land was cut up by watercourses and of course for part of the year the valley was underwater.

      Alexandria was a little fishing village when Alexander conquered Egypt.

      1. “The wind usually blowing upstream” is an exaggeration. The river and branches meander, and the wind shifts.
        Yes, the river is good for returning empty barges upstream. But reliably getting horsemen, especially horsemen exchanging horses with urgent messages along?
        And the black land, as mentioned, is cut up by ditches and flooded during floods.
        Note that the Persian road does not go mostly through black land. It goes from Pelusium to Memphis – at the edge of the desert. Avoiding the canals – except the short stretch across Nile to Memphis on opposite shore.
        But a route at that will, at minimum, need stations with rested horses and rested couriers.
        Beyond that… Is the natural edge of desert actually straight, easy to ride on and well watered year round? Or do you have opposite things – here a dune wedging in between irrigated fields, there a ditch carrying water between dunes, ditches which carry water during flood but are parched and dry at low water?
        Would it have made sense for Romans or Ptolemies to actually construct desert edge road to be straight, ridable and supplied with large amounts of water all along? To meet the use case of, say, urgent horseback messenger from Pelusium to Alexandria to report a Seleucid invasion, and urgent mass of a couple of thousands horse back the same way?

  22. The roads were one of the benefits of Roman rule, alng with baths and indoor plumbing.

  23. > a trip of approximately 2,500km (1,550 miles, give or take) in twelve days
    > (by exchanging not only horses, but riders, as it moved).

    To put this in perspective: with modern communications this would require an empire stretching to the Oort cloud.

    PS: a typo: “able to grab” should be “able to brag”?

  24. Did the Romans have an equivalent of Eminent Domain? What happened if someone had something in the route of the road you wanted to build?

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