> ## Content Index > Fetch the complete content index at: https://romanempiretimes.com/llms.txt > Use this file to discover other available public pages before exploring further. # Roman Roads VS Modern Highways: Which Are More Straight, Or Bend Less? - URL: https://romanempiretimes.com/roman-roads-straight-modern-highways-straighter/ - Published: 2026-10-12T23:09:00.000Z - Updated: 2026-10-12T23:08:59.000Z - Description: A study of Roman road alignments finds they have quite an impressive performance versus modern major roads, with terrain and construction explaining the gap between them. - Author: George Liapis - Tags: Roman Empire News, roman roads, engineering, the appian way, Itiner-e, Pannonia, Alps The familiar image of a Roman road is a ruler-straight line across the landscape. A study published in *Nature Communications* in September 2026 tested that image against a detailed map of routes across the former empire. Its finding is striking: Roman roads usually took direct courses, but the major modern roads used for comparison are straighter still. The researchers measured how much each route bends over stretches of one kilometre. On that scale, mapped Roman roads had an average sinuosity of 1.048, while the comparison set of modern major roads averaged 1.024\. A value of 1 means a perfectly straight line. With the use of modern advanced tools, this seems like a logical win for the modern network; however, when compared to the tools Ancient Romans had in their possession, their feats are extraordinary. Roman engineers pushed their times' technology into the limits, and often pursued direct alignments, especially on level ground. What changed between a road built for people and animal-drawn traffic and one built for motor vehicles was the ability to reshape difficult terrain, and the speed at which a bend could be taken. ## What Counts as a Straight Road? Sinuosity compares the actual distance along a route with the direct distance between the same two endpoints. The study divided roads into one-kilometre sections before calculating it. A road following a direct line scores 1; a route that winds between its endpoints scores higher. Using the same short interval across both networks lets bends in different landscapes be compared on a common scale. The Roman median was extremely close to a straight line than the study's average. The modern median managed to beat it, but quite closely. That pairing shows that many sampled sections in both networks were almost straight, while more winding stretches pulled their averages upward. These comparisons describe short stretches, not unbroken city-to-city routes. The modern comparison covered paved major roads and highways, with selected local roads in some areas. The Roman side came from Itiner-e, a scholarly atlas assembled from archaeological reports, ancient itineraries, milestones, maps and remote sensing. Its mapped lines cover roads used during the Roman period, including some older routes that the Romans adopted. ## The Straightest Roman Lines Crossed Open Country The lowest sinuosity values appeared largely in lowlands. The study identifies western Europe, the Pannonian basin, North Africa, the Po valley, Puglia, central Anatolia and Syria as areas where road courses could remain direct over easier ground. In the plains of northwestern Europe, roads often extend radially from settlements, making their geometry especially apparent on a map. Roman main roads were a little straighter than the secondary roads in the dataset. The difference is modest, but it fits a system in which important long-distance connections received more deliberate alignment and construction. Itiner-e classifies main roads chiefly through evidence such as milestones and ancient itineraries; its secondary category includes the smaller connections that served local movement. The Appian Way is an accessible example of a planned Roman artery, beginning with the Rome-to-Capua road of 312 BCE. Its long direct stretches help explain why straightness became part of the Roman road's reputation, while its changing course across Italy shows why a named road should not be imagined as a single drawn line. Our account of [the Appian Way's route and later history](https://romanempiretimes.com/the-appian-way-europe-most-travelled-road-is-not-a-modern-highway/) follows that road beyond the view of one surviving stretch. ![Straight stone-paved Via Appia receding between grassy banks near Santa Maria delle Mole, Italy.](https://storage.ghost.io/c/aa/80/aa80281a-abce-4f35-865f-05153c8cc335/content/images/2026/10/via-appia-straight-road-santa-maria-delle-mole.jpg) Straight stretch of the Via Appia between Ciampino and Santa Maria delle Mole, near Rome. Photo: [Gigi er Gigliola / Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Via%5FAppia%5FSanta%5FMaria%5Fdelle%5FMole%5F-%5F1.jpg?ref=romanempiretimes.com) ([CC0](https://creativecommons.org/publicdomain/zero/1.0/?ref=romanempiretimes.com)). ## Hills and Passes Changed the Route As slopes increased, the mapped Roman roads tended to become more winding. Mountains pushed routes towards valleys and passes; in several provinces the dominant road direction followed the orientation of the ranges. The study points to high-sinuosity routes in mountainous parts of southeastern Europe, a marked contrast with the lowland lines elsewhere. A bend could also protect a usable gradient. The paper reports that 90.57 per cent of the mapped road length falls below its upper 16 per cent slope threshold for possible wheeled traffic. That threshold is the generous end of a scholarly range, but the pattern shows why a route for carts and wagons might follow a valley or make a longer climb instead of taking the shortest line up a hillside. The Alpine roads offer a revealing case. Despite crossing Europe's highest mountain system, their average slopes in the study were lower than those of roads mapped in several other ranges. The researchers point both to favourable longitudinal valleys and passes and to substantial Roman work on the approaches. A straight-looking road was the result of choices about gradient as well as direction. ## Straight Lines Also Took Engineering Roman surveyors had instruments and methods for setting out direct alignments, and builders could intervene where the ground resisted. The study cites cuttings, terraces, retaining structures and occasional tunnels, particularly in the road system of the Aosta Valley. Such work helped carry a route through or across difficult ground while keeping it usable. These interventions were selective. Following a natural corridor could give travellers a gentler ascent with less excavation, even if the line curved. On a ridge, by contrast, a relatively direct course might be possible above more complicated slopes. The analysis found a relationship between sinuosity and maximum slope; gradient, corridor and construction all helped determine the route. Our earlier account of [how Roman builders surveyed and constructed roads](https://romanempiretimes.com/all-roads-lead-to-rome-how-did-romans-build-their-roads/) describes the practical work behind a straight alignment. The new measurements add a landscape-wide view: they show where direct routes were common and where engineers allowed the terrain to determine the line. ![Straight stone-paved section of the Via Egnatia rising gently between vegetation near Peqin, Albania.](https://storage.ghost.io/c/aa/80/aa80281a-abce-4f35-865f-05153c8cc335/content/images/2026/10/via-egnatia-straight-road-peqin-albania.jpg) A straight stone-paved stretch of the Via Egnatia near Peqin, Albania. Photo: [Carole Raddato / Wikimedia Commons](https://commons.wikimedia.org/wiki/File:The%5FVia%5FEgnatia%5Fnear%5FPeqin,%5FAlbania%5F%2838889212724%29.jpg?ref=romanempiretimes.com) ([CC BY-SA 2.0](https://creativecommons.org/licenses/by-sa/2.0/?ref=romanempiretimes.com)). ## Why Modern Highways Bend Less The study's modern major-road network has a mean sinuosity of 1.024 and a median of 1.0026, both below the Roman figures. Its authors connect that result to modern surveying and construction, which can cut, fill and otherwise alter terrain on a scale unavailable to Roman builders. Roads intended for faster cars also avoid sharp turns where the route and terrain permit. The Roman routes were designed around different vehicles, materials and constraints. A line that climbs too sharply for a loaded wagon would offer little benefit merely because it looks short on a map. The study's slope findings show that Roman builders repeatedly found practicable gradients through difficult country. The contrast is clearest when the same principle is applied to two periods. Both sets of builders sought workable, direct connections. Modern engineering can spend much more effort changing the ground to preserve one. The result is a smaller measured deviation from a straight line across the major roads sampled today. ## A Map That Makes the Reputation Measurable The 2026 analysis used Itiner-e's nearly 300,000 kilometres of mapped Roman routes, the same research base discussed in [our report on the empire's wider road network](https://romanempiretimes.com/roman-road-analysis-empire-not-centred-on-rome/). That earlier report covers the location of the system's main corridors and the position of provincial cities. Here, the revealing result lies in the shape of the roads themselves. Itiner-e's detailed lines follow known remains and plausible courses through real terrain. Many alignments are reconstructed from several kinds of evidence; only 2.737 per cent of its mapped length has a location classed as certain. The straightness study found broadly similar patterns when it separated roads by certainty and type, while the atlas leaves room for excavations and field survey to sharpen individual routes. For now, the measured picture is clear. Roman roads were exceptionally direct where the land made that practical, and their builders sometimes cut or supported the ground to maintain a usable course. The next bend was often a response to a pass, valley or gradient. Modern highways show what happens when builders can alter more of that landscape to keep the line straighter. 🏛️ ****Sources used:** [Adam Pažout et al., “Network science reveals the structure and lasting impact of the Roman road system,” Nature Communications 17, 9551 (2026)](https://www.nature.com/articles/s41467-026-75453-3?ref=romanempiretimes.com). [Pau de Soto et al., “Itiner-e: a high-resolution dataset of roads of the Roman Empire,” Scientific Data 12, 1731 (2025)](https://www.nature.com/articles/s41597-025-06140-z?ref=romanempiretimes.com). [UNESCO World Heritage Centre, “Via Appia. Regina Viarum,” Brief Synthesis (accessed 11 October 2026)](https://whc.unesco.org/en/list/1708/?ref=romanempiretimes.com).