Marlborough College Summer School

Roman Roads

'All roads lead to Rome' – tribute to a phenomenon that held a world empire together. But who built them and how were they planned and maintained? Logan Thompson tells us more.

A Roman street in Pompeii
A Roman street in Pompeii

For many centuries, the expansion and protection of the Roman Empire rested upon the broad shoulders and discipline of heavy infantry legionnaires. It was due to the efforts of these carefully recruited, ruthless, tough, highly trained and well-led soldiers that Roman civilisation advanced and developed unhindered.

It was these legionnaires who ultimately ensured efficient, uniform administrative standards, gigantic ambitious building projects, mesmeric but succinct Forum oratory, a guaranteed peace and real certainty of its continuation for the majority, and an extremely, luxurious and decadent life-style for the few. Without the powerful army, one of the best in history, and certainly the most effective for the longest period, none of the former would have been possible. The primary reason for such military effectiveness was the metalled roads the soldiers constructed and upon which they marched. Why, and how, did the Romans devote so much time, physical effort and considerable funds to developing extensive route networks, and how were these planned, built and maintained?

The principles of firm road construction arose because unmetalled paths and tracks could not withstand passage of large numbers of horses, carts and infantry. Such routes soon disintegrated, particularly in wet weather, into deep mud which seriously impeded a unit's movements. Accurate staff movement calculations could therefore not be made, and campaign planning was impeded. Firm, paved roads, however, resolved these problems and guaranteed movement of very heavy traffic. As a result, armies could progress twenty- five miles a day, even in inclement weather conditions, rapidly reaching distant areas in which unrest had been reported. Knowledge of the army’s ability to achieve this was itself often a major deterrent to the development of hostilities.

Eventually, a most comprehensive road network embraced the entire Empire. Roman governments could thus control their territories and population with an army of 180,000 legionnaires, plus auxiliaries – a figure markedly out of proportion to the total population of 55 million. Good roads thus saved both time and expensive military manpower.

Metalled routes also ensured unimpeded movement from a tactical viewpoint. If a road network existed towards a campaign area, all arms groups could move to it in battle order, at high speed, behind a screen of auxiliary cavalry. Consequently, when contact was made with an enemy situated near the route, forces could be rapidly deployed into battle formation and commence fighting with little delay. The marching rate, whilst carrying over 60lbs of equipment, was either twenty miles in five hours, or, when forced-marching, twenty-four miles in the same time. Legionnaires were trained to fight effectively immediately after such marches. In troubled areas, roads afforded the essential means of rapidly resupplying isolated camps and forts with vital information, equipment and food.

Speed of transmissions being vital; roads were a crucial means of passing essential information. Messages from the emperor, or his high officials, were delivered by couriers of the Cursus Publicus, the Imperial communication service. This organisation spanned the entire Empire utilising post houses and inns along major routes. Post houses, where a horse could be changed, were sited every ten to fifteen miles. Inns (mansiones) provided accommodation and were the Roman equivalent of motorway service stations. These were found at twenty to thirty-mile intervals. Their catering was good too. Suetonious (AD75-160), the Roman biographer and antiquarian, states:

Vitellus would display his gluttony in wayside taverns seizing almost from the very fire dishes that were still steaming, or leftovers from the day before, and half eaten food.

So, post houses and inns enabled couriers to travel approximately fifty to sixty miles daily. Provincial governors were responsible for correct maintenance of all aspects of main routes.

Private individuals were only allowed to travel by the Imperial Post if issued with a special permit. The seriousness with which this rule was enforced is illustrated by letters between Trajan (emperor from AD98- 117) and Pliny. Pliny wrote from Bithynia inquiring if outdated permits could be used as he was anxious not to hold up important despatches. The emperor's response was short and curt, he stated; 'It is my invariable rule to have fresh permits sent to each province before the dates are required'.

Roads enabled transmission of critical intelligence and orders from headquarters to camps, forts and moving troops. Messages were additionally sent via signal stations, but these were naturally restricted by content brevity, and foggy or misty weather.

The first proper Roman road was constructed in 312BC during the Samnite wars to provide fast, reliable communications and supply links between Rome and Capua. This was the Appian Way later extended to Brindisi. The Samnites were a particularly formidable foe whose well-armed soldiers had inflicted a crushing defeat upon the Romans at Caudine Forks in 321BC. Perhaps this contributed to the road building decision. The route followed a remarkably straight, direct, well-drained 122 mile course, firmly topped with neatly fashioned blocks of volcanic lava.

It is commendable that Roman engineers and surveyors managed, with their first-ever route, to incorporate most of the construction principles so closely followed during the next 700 years. Thereafter, route networks constantly expanded in every direction, like the spokes of a wheel, with Rome as the hub. Construction of military service routes, based upon deep foundations, was generally governed by strategic and operational circumstances. They often followed the courses of victorious military campaigns. This was so in Britain. Keith Branigan explains; the routes were Watling Street from Richborough via Canterbury, London, St Albans, Dunstable, Towcester to Wroxeter; Ermine Street from York and thereafter Scotland. From London to the south-west was via Staines, Silchester, Salisbury, Dorchester linking up with the Fosse Way at Seaton.

Major camps or existing settlements would often be incorporated with the new routes. Eventually, lateral/link roads increased network size by embracing other town sites and forts. These hastened the pacification process whilst providing easier travel to larger numbers of the population. Road repair and building programmes continued constantly until the Empire reached its maximum geographical expansion. By then, some 55,000 miles had been built. Therefore, when the phase of empire consolidation took place excellent routes remained beyond the new boundaries, for example in Scotland. These enabled areas forward of the Roman boundaries to be dominated, and were of great value when major forays were made beyond the new frontiers. For instance, during the genocide campaigns of Septimus Severus in Scotland between AD208 and 211.

The greatest potential expense in terms of construction costs was manpower. However, this was actually reasonable because surveying, engineering, stone quarrying and hard physical tasks were done by soldiers. In newly conquered territories slave labour was also utilised. Furthermore, road and fort or camp building and maintenance was a routine part of a soldier's duties – almost equal in importance to fighting and training.

Troops, being paid, were automatically expected to perform these tasks whenever necessary. Consequently, when no priority duties were out- standing after barrack administration, patrolling and training etc, route maintenance and road building tasks were done.

Periodic expenditure was sometimes necessary but such costs seem to have been containable. Sometimes important people contributed financially to road repairs. Suetonius states that Emperor Augustus (27BC-AD14) arranged for repairs at his own expense to the Via Flaminia as far as Arminium, the other roads being shared out amongst the generals honoured by a triumph, who had to find the money for this out of their battle spoils’.

The Roman central government, throughout the Empire period, made a top priority of efficient military service routes maintenance. Consequently, road repairs continued to be undertaken until alter the Empire fell. For instance, tasks were undertaken at the end of the fourth century on the road near Goathland in North Yorkshire, including the resupply of route gravel dumps. 1t is probable that regular military service route maintenance continued in Britain on a major scale until at least AD409. This is particularly likely in tactically sensitive areas, for example the Solway defence line, which was manned until about AD425.

Evidence I have observed from towns indicates that some roads therein were resurfaced until as late as the fifth century. As Peter Salway mentions in his book, The Illustrated History of Roman Britain:

The fact that Rutilius Namatianus, early in the fifth century, considered it as worthy of special comment that the bridges were still down and the posting-inns were deserted in Italy after the sack of Rome by Alaric suggests that, to his Gallic correspondent, such a failure in the system would still have seemed unusual in AD417.

So it would appear likely that far from a 'rise and fall' of Roman roads during the Empire period, they continued to the end in a state of efficiency similar to that achieved in the second century, including the various services based upon them.

All military service routes were planned and constructed by the army. Military engineers and surveyors possessed considerable experience and knowledge of the techniques involved. Essential prerequisites of route planning were that each should: be as straight as possible, remain close to one contour throughout their course to reduce additional soldier and horse fatigue, avoid swamps, marsh, forest, hills, spurs, and knolls wherever possible. These principles ensured a selected route was short, flat and straight for the majority of its course. It was not, naturally, always possible to achieve the ideal, hence the periodic use of sudden sharp bends to avoid obstacles. Once these were circumnavigated the road reverted to its planned line. Cuttings and viaducts were sometimes employed to maintain a straight road.

Mountainous or hilly terrain caused particular problems. In such areas, for instance, the achievement of a level track was sometimes sacrificed in favour of a straight route. As a result, a. few sections of some roads soar majestically and irrepressibly straight up steep slopes, then dramatically downwards before rushing up the next slope thus creating an exhilarating switchback course. The shorter route advantage was obviously offset by the greater exertions imposed upon subsequent travellers.

The route from Tavira (in southern Portugal) to Alportel necessarily rises, winds and bends through very hilly country. However, fascinating on-ground study reveals how surveyors managed, whenever possible, to create the maximum number of straight, albeit short, sections. In Hungary, generally a land of flat plains periodically punctuated by high knolls, engineers' tasks were probably easier, hence magnificent stretches of long, straight routes. Nonetheless, even these periodically make sharp bends to avoid contemporary problems, the causes of which are no longer apparent today.

Legionnaires were thoroughly practised in road building, whilst many were qualified tradesmen such as carpenters and stonemasons. These attributes obviously assisted the performance of non-military administrative tasks. This is confirmed by the only extant Roman soldier ever discovered, at Herculaneum, in 1980. He died when Vesuvious erupted on August 24th-25th, AD79. J.W. Deiss in his Herculaneum book mentions the comments of Dr. S. Bisel. After a lengthy and expert forensic examination the following characteristics were established:

He was about 3, years old, 5 feet 8 1/2 inches tall, well nourished, strong and tough. The carpentry tools on his back included a hammer with attached adze, two chisels and a hook for pulling down tree branches. He had his sword and dagger. Heavy muscle build up of the forearms was indicated by the way the bones had been remodelled to accommodate musculature needed for heavy work perhaps also for holding sword and shield in the drill position.

The first surveying task for grommatici (surveyors) was to plot and mark out the new route course from points A to B. Territory was usually surveyed in straight sections within the planned overall long-distance route with alignment changing direction at necessary or convenient sighting points. Naturally, the best use was made of local terrain. This involved gathering topographical information, a frequently difficult task, due to the presence of hills, forests, and marshes. Surveyors used theodolites (instruments for measuring horizontal angles), and portable sundials for direction finding. This combined with detailed reconnaissance and smoke lines enabled a route course to be selected. Thereafter, all available manpower was assembled. This usually involved one entire legion (6,000 men), plus a similar number of supporting auxiliaries and slave labour. In pacified provinces, civilian contractors were hired to assist, particularly with movement of stone from quarries.

The first construction task was clearing trees and undergrowth from the route line. In heavily wooded countryside, which surveyors had been unable to avoid, the task was an exceptionally arduous one. The second phase was to dig a trench along the route to facilitate the foundation construction. The depth of this depended upon the existence and height of the natural rock strata. If present for long distances in the right direction, for example on Wiltshire chalk, the legionnaires task was much simplified. The effort of moving thou- sands of tons of soil, in an era lacking earth-moving equipment, was enormous. The accuracy of route direction planning was amazing. For example, as Keith Branigan mentions, the Fosse Way from Exeter to Lincoln never deviated more than six miles over its entire length of 200 miles.

Materials were generally those available near the proposed route. In Britain, legions serving in the North frequently employed limestone, sandstone and granite, whilst in the South they used flints and chalk. To make firm foundations the base of the deep route trench was packed with large stones bonded with mortar. Upon this was laid several layers of successively smaller stones, also mixed with lime to produce a particularly tough, waterproof binding agent. This was frequently used in tasks requiring extra strength such as walls, arches and foundations. However, in areas where rock or chalk formations provided a firm natural base the depth of man-made foundation trenches were acceptably shallow.

In certain areas, such as Italy, North Africa and Turkey, most road surfaces were comprised of neatly-laid, level paving stones.

Roads in Britain were usually surfaced with a mix of gravel and sand, or broken flints and little pebbles. Nonetheless, a few routes, such as the Blackstone Edge near Rochdale, and a recently excavated section of the Fosse Way near Axminster, were metalled. The latter revealed a 50ft wide section with cobbled surface and drainage system upon both sides. Some roads, like the one near Goathland in North Yorkshire, were topped with fairly flat stones similar to those used in Lake District dry stone walls These were covered with sand to fill the cracks between stones, and finished with gravel. Roads were sometimes built up above the surrounding countryside (highways) to afford better surveillance for troops and to deter ambushes.

Road crowns were higher than the sides to facilitate rainwater removal. Water flowed to the road edges where it passed into the flanking drainage system. In very wet areas, road crowns were even more pronounced. Verges were often denoted, and the road supported by, high upright stones. The Romans were always concerned about efficient drainage. Route sections across low ground liable to flooding would be constructed on a built-up embankment called an Agger, to prevent road immersion and to achieve drainage flow. In the only letter from The Vindolanda Trust concerning roads (No 946) written in AD110, Octavius tells Claudius that: 'he cannot collect his goods from Cataractorium (Catterick, an army base where shoes and uniforms etc. were made) while the roads are so bad (dum viae male sunt)'. Perhaps this problem was caused by horizontally sheeting rain and high winds for which the area is still renowned!

Road widths depended upon the volume of prevailing two-way traffic. New routes were about 20 to 23ft wide, sufficient to accommodate legions marching in six-man wide columns, and their supporting equipment supply wagons. When civilian traffic developed, and then increased appreciably, it was often necessary to widen existing routes to cater for the new volumes. Possibly, the army would sometimes be involved in such tasks. The new road width would probably then be about 40ft wide.

Despite extreme care taken by surveyors and engineers, some routes would inevitably encounter natural obstacles. Streams were traversed by sturdy, miniature bridges upon which stones and gravel might be laid. Small rivers were often crossed by paved fords at shallow points. Wider rivers were spanned by long wooden bridges supported either by masonry columns or robust timber piles. Sometimes, particularly at important towns, these were later replaced by magnificent stone bridges, such as the Fabricus over the Tiber, at Tavira and Aldwincle in Northamptonshire.

Unavoidable marshes and swamps were often overcome with stout wooden pontoons upon which bridges were laid. Viaducts acting as long bridges were constructed to negotiate wide obstacles such as a series of hillocks interspersed with marsh. Whilst campaigning, army engineers frequently made pontoon bridges using several small boats which were secured together and attached to both banks. A long series of planks were laid together on top of these, providing an emergency bridge. Occasionally tunnels, or cuttings, were dug through mountains, or spurs, to maintain a level, straight route section.

Roman roads were so well made that little repair work was actually necessary, except on the wooden bridges. Many were still in perfect working order centuries after their construction. Nonetheless, once a route was finished it became the task of the local authority (civitates) to maintain it. Private roads linking farms, villas and small villages to main routes were the responsibility of the landowners to build and maintain. There were doubtless exceptions to this principle when legions were not on active service but had to be kept occupied. Despite periods of most rigorous combat training, there was still opportunity for units to undertake useful community tasks which practised soldiers' artisan skills. Bridge building, road widening, and new route construction was therefore most probably undertaken. These benefited the local population, maintained military engineering skills and improved civilian/military relations.

Milestones – tall, round stones set upon plinths with details either engraved or painted upon them – were the means whereby travellers could check route destination and distance information. Keith Branigan says that local authorities usually established these, mentioning upon them the name of their authority in abbreviations, for example, Respublica Civitatis Doburronum – RPCD – was inscribed upon milestones found at Kenchester in Hereford, and at Worcester. Very often, the name of the ruling emperor at the date upon which the stone was erected was also marked. At points where three routes met (tria via) a noticeboard would be set up upon which all recent important news was reported. Hence the origin of our word 'trivia'. A Roman mile was calculated at 1000 double paces, making 2000 paces. Thiis equalled 1481.5 metres or 1620 yards.

Road control duties were undertaken by detached, seconded regular soldiers. The beneficarious was a military police officer with special responsibilities for traffic control on main routes, major junctions, frontier posts and the maintenance of police posts. The singularis was an official messenger and overseer of supply routes and communication links. The military policemen working under these officials were called speculatores.

Details of all Empire main roads are shown upon the Peutinger Table. This is a twelfth-century copy of an original document of about AD217. This fascinating scroll map is an accurate guide to all main routes covering the entire Empire. Over 500 towns and relay stations are mentioned. The map is enhanced and amplified by the Antorine Itinerary, compiled around the same time, which is a military route selection manual for the assistance of couriers.

Romans were accustomed to long journeys and how to plan them in the most comfortable way. Pliny the Younger (AD62-114), a friend of Tacitus, when travelling with his entire staff to his appointment in Bithynia, wrote to the Emperor Trajan that he had decided to travel partly by carriage and partly by coastal boat: 'for the great heat makes it too difficult to go all the way by road and the prevailing wind prevents me from travelling entirely by sea'. Road conveyances were numerous. They comprised mules, donkeys, horses, carts, carriages and chariots. Heavy loads were often moved in a. slow but sure way on large wagons pulled by oxen or mules. A light cart drawn by one horse could cover about fifteen miles a day. Imperial messengers travelled by horse, or light carts drawn by one, two or even three horses. Larger carriages, pulled by two or more horses or mules, could cover up to seventy-five miles a day.

The Roman Empire generally possessed strong central governments and a single, stable currency. The scale of inter-provincial trade was substantial, whilst export and import volumes were remarkably high. The manner in which the latter were achieved was extremely efficient and sophisticated. Goods were constantly and simultaneously being moved from one country to another. For example, Britain exported jet jewellery, hunting dogs and warm woollen cloaks, whilst importing wine, fish sauces and decorated Samian tableware. This large trade movement was facilitated by widespread river and canal systems; large merchant ships carrying goods from well-organised ports to others overseas; and the elaborate road systems. Roads provided the initial, and final, means of trade movements.

Once province routes were established and the network enlarged with link roads, a villager who could walk easily to a little town by road and sell his vegetables, for which he was paid in coin, might eventually perhaps purchase one Samian plate from GauL Province populations thus contributed to and benefited from overall trade development and the Empire trading systems which would not have been possible without the road networks. Furthermore, small settlements (vici) which sprang up adjacent to Roman camps and mansiones would not have enjoyed a constant rise in prosperity.

Route systems contributed significantly to fostering economic development and were a vital link in the sophisticated, well-regulated trading routes, an essential means of spreading a civilised outlook, and inculcating much improved living standards for millions of citizens. As Peter Salway observes:

An enormous amount of archaeological material from Roman sites throughout the Empire, including Britain, proves the mass distribution of goods over long distances, and a high proportion must have gone to private individuals.

A Lockhead Company advertisement, in the Financial Times recently, well summarised Roman road building achievements: 'All the roads they built, including minor ones, would encircle the Earth ten times, and many of these lasted without repair for 1000 years'. Much of their route network has been used for centuries, thus bequeathing to twentieth- century engineers a system providing correct directions and firm foundations. The Romans made life easier for us. They fully realised, of course, that firm roads guaranteed heavy troop movement towards operational areas. Above all, they appreciated that 'flexibility is critical to an efficient defence. Julius Caesar understood it. All Romans understood it'. Without their route network the Roman Empire would not have lasted as it did, for the mere knowledge that legions could be on the scene within weeks was usually sufficient to keep the peace.

To travel upon a Roman route system is an invigorating and fascinating experience; a constant and vivid reminder of the accuracy and efficiency of Roman engineering, where no obstacle was insuperable. No wonder that our Anglo-Saxon forebears regarded them with astonishment and uncomprehending bewilderment, concluding that they must have been built by giants.

Logan Thompson is a freelance journalist and historical researcher.



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