The Romans in Britain: How were Roman roads built?

One of the things the Romans built all over their Empire were ROADS.

There were no proper roads in Britian before the Romans came. There were muddy tracks that wound along from village to village, but these were no good for getting places quickly.

Roman rulers needed to be able to control their Empire - they needed to send messages to regional governors quickly, they needed to transport goods and products from place to place efficiently, and they needed to move their legions to put down rebellions and defend against attacks very rapidly. To do all these things, the Romans built good quality roads. The easiest and fastest way is to build a straight road - so that is what they did.

How were Roman roads built?

Here is a cut-through of a roman road.

The bottom layer is made from compacted sand or dried earth. Next comes a layer of crushed rock, then gravel mixed with a cement mortar. Above this is placed a layer of finer gravel mixed with sand and more cement. On the top are placed large flat stone slabs, fitted closely together. There are kerb stones placed at either side to mark the edges of the road. Beside the road is a drainage ditch to allow rainwater to drain away from the road easily. The road was about 24 feet wide - wide enough for a column of soldiers to march along, with room to spare for chariots to go by. The road was built up about 5 feet above the land. This helped drainage, but also allowed soldiers on the road a good view of what was on either side, to avoid being ambushed.

Some of the major roads we drive on today follow the same route that Roman roads did. You can usually tell if a road was once a Roman road if the road is very straight for a long distance. Roman roads were built so well that they lasted for hundreds of years. In fact some of these roads have only been resurfaced a few times since the Romans built them.

How did they build them so straight?

Roman roads are usually built as straight as can be from one point to another, only bending around very steep hills. Before building, a Surveyor would mark out the position of where the road should be built with a set of sticks. The surveyor used a tool called a Groma.

A Groma is made from a long pole with a spike on the bottom for sticking into the ground. At the top is a cross, with a string hanging a weight at the end of each arm of the cross, and onother weight on a string at the centre.

The surveyor could stick the spike into the ground, then look across a set of three strings. If all three strings were hanging in the same line, then the surveyor knew he was in an exact straight line from his marker. If the strings were not hanging together then the surveyor would need to adjust his position until they were exactly right. He also use the Groma to mark out accurate 90-degree right-angles for buildings. Roman surveyors were very skilled, and had to learn how to use the Groma properly.

Why not have a go at making a Groma for yourself? You will need...

A pole
Some strips of wood to make a crosspiece and a support arm
Some string
Modelling clay to make into weights.

When you have made your Groma, you could try marking out straight lines across the playground.

Roman Roads

THE FIRST ROADS in Britain were built by the Roman legions, which had their own surveyors, engineers and the equipment they needed for this type of construction work. The availability of local materials dictated the details of road construction, but the basic principles were always the same. The road took the form of an embankment, raised above the level of the surrounding land, with drainage ditches on either side. It would be built up in a series of layers, comprising a foundation of large rocks, followed by smaller stones, gravel and sand laid down in successive layers and rammed into place.

A cobbled surface was commonplace in towns or areas of heavy use, but usually it would be gravel. The embankment was cambered for drainage, often 10m (33ft)or more wide; it was rarely less than 3m (91⁄2ft) wide to allow room for two-wheeled vehicles to pass. As elsewhere, Roman roads in Britain were built as straight as possible. The Roman surveyors had no need to worry about who owned the land along the route-way because as conquerors they could choose the most direct route. Nevertheless, they by-passed mountains, marshes and forest, where they posed particular obstacles, and they would seek out suitable crossing points at rivers.

Although their primary purpose in the early days of the conquest was to speed the movement of troops, roads subsequently became even more important as communication routes between different parts of the empire. They enabled important information to be passed between Rome and the provincial governors of the areas under their control. In Britain, the Roman economy was agricultural, based around villa estates, which produced surplus food to provide supplies for the army and the urban populations. The roads also made possible the movement of pottery and other goods, whose production became commonplace in Britain in the third and fourth centuries AD.

Well-known Roman roads include Watling Street, which ran from London to Chester and the Fosse Way, which crossed England from Exeter in the south-west to Lincoln in the north-east. The latter followed a route in use since prehistoric times and around AD47 it marked the first boundary of the new Roman province. Roman roads later became a liability because invading barbarians could travel along them as quickly as the Roman armies. The Salisbury–Badbury road was deliberately blocked by the Bokerley Dyke during a crisis in the fourth century. The roads went into decline after the Roman departure and not until the advent of railways in the nineteenth century did Britain again enjoy such an efficient communications network.

This reconstruction (above) reveals the benefits of Roman civilisation. The central feature is the road which provides easy transport for troops and commerce. The legionary cavalry soldier, accompanied by a foot soldier, is of high status and would have a cohort of legionnaires not far behind him. In the distance you can see the classical design of a villa which represents the beginning of an architecture that was new to Iron Age Britain.

A small settlement takes advantage of the passing traffic. A woman is selling food and drink and you can see the amphora containing oil and wine – examples of imports introduced by Roman merchants. The buildings are roofed in tile and some have painted plaster. However, despite these innovations, you can also see Romano-British carrying on with their lives, emphasising that not every aspect of British life was romanised. The soldiers pay in coin – most likely small denomination bronze-copper alloy coins, received as change after paying taxes with silver or gold coins received as wages. The soldier on his knees in the foreground has lost the gold coin that represents a month’s wages – it will be this coin that will be found 1800 years later. The road is the Fosse Way – still a major route today. As in Roman times, it links up with a system with London as its hub.