Roman Britain

According to Hugh Davies in Roman Roads in Britain (Shire Archaeology, 2008), the Romans began building a network of roads in Britain “almost as soon as they arrived” (p. 6).

What we know about Roman roads are based on modern archaeological evidence and investigation, as there are few surviving documents about the Romans’ engineering feats.

The Romans invaded Britain–then referred to as Britannia–in 43 AD, and would rule the island as a province of the empire for nearly four centuries.

In Britain, the roads were built the same way they were built in other areas of the empire: in the form of an embankment, and as straight as they could manage it.

Building the Roads

Just two years before the invasion, Caligula, who had drained Rome’s coffers on expensive projects and planned to appoint his beloved horse as consul, was assassinated by the Praetorian Guards.

Britain was an exotic and mysterious place in the Roman imagination, according to the BBC’s Dr Neil Faulkner, and Caligula’s successor, the unpopular Claudius, turned to this mysterious place to prove his military might and get the Senators on his side.

The Roman army sent to Britain was composed of 40,000 professional soldiers and began the invasion with a landing at Richborough in Kent. (Archaeologists still debate whether they also landed in Chichester in Sussex, or if they landed in Chichester first.)

The Catuvellauni was the dominant tribe in Britain at the time, controlling what is now Hertfordshire, Bedfordshire and southern Cambridgeshire, and probably Buckinghamshire and parts of Oxfordshire as well. They may have been the same tribe that faced Julius Caesar in 54 BC, before he was called away from Britain to Gaul to deal with the Gallic Wars.

In 43 AD, the Roman army anticipated opposition from the tribe, who were based in their capital, Colchester. The Romans called the tribe’s capital Camulodunum, the “Fortress of the War God Camulos”. Camulos was a Celtic god that the Romans equated with their war god, Mars.

To get to Colchester from where they were beached at Richborough, the Roman troops had to move up the Thames, establish a crossing, and turn north-east (Davies, 2008, p. 11).

Watling Street

This meant they had to build roads, and the road they built to reach the Thames is today known as Watling Street.

It was one of the greatest roads in Britain in Roman and post-Roman times, running from Dover to London, and northwest via St. Albans (Verulamium) to Wroxeter. Watling Street would later have a monument, large enough to be visible to those approaching from the sea, and a fort (p. 11) .

The tribes had settled and lived in Britain for centuries, but the existing paths they used did not suit the Roman army’s needs. The Romans needed roads that were still passable in bad weather and strong enough to withstand wagon wheels even when it rained. Roman surveyors and engineers built roads higher than surrounding land, inclined slightly from the centre to allow rainwater to flow into drainage ditches on either side.

The raised mound was called the agger and was covered with metalling, a hardy layer to protect the ground underneath. This technique is still used in road-making today. While nowadays we would be using concrete, the Roman engineers made use of available material and layered loose stones or gravel over the agger. The roads were regularly maintained by replacing the metalling to guard against wear and tear.

To fit two-wheeled vehicles, the roads were built to be at least 3 metres (9 1/2 feet) wide; often, they were wider than 10 metres (33 feet). The average width of Watling Street, for example, is 10.1 metres (Davies, 2008, p. 42).

The Romans also set up milestones, inscribed with the name of the emperor (p. 30). Unfortunately in Britain, only a small number remain in their original positions, as others have disappeared or were simply discarded.