Generally there was an embankment (agger), raised above the level of the surrounding land but this also could be a terrace cut into a hillside. There were usually drainage ditches on either side. The agger would be built up in a series of layers often comprising a foundation of large rocks, followed by smaller stones, gravel and sand laid down in successive layers and rammed into place however in detail there is much variation presumably due to availability of local materials. Like modern roads roman roads had a camber to shed water from the surface. Agger widths varied from about 5 metres to more than 10 metres presumably in response to traffic volume and importance. There were often two more ditches set some distance from the agger perhaps to define some sort of wider road zone. Initially roads were built to facilitate rapid movement of military forces and supplies between forts and to troops in the field during campaigns.
It is a myth that roman roads are always run in a straight line. It is true that roman engineers always tried to follow the most direct route possible between two points but were quite happy to go around hills and zig zag up and and down steep slopes. It is true that roads tend to be made up of a series of straight sections. In fact at the start of our project area the road makes a sharp bend because the Romans decided it was more sensible to go round Pendle Hill.
When was our road built
The Romans came to Britain in AD. 43 our local tribe was the Brigantes whose lands probably occupied most of northern England on both sides of the Pennines. For the first couple of decades the Brigantes led by their queen Cartimandua allied themselves with the Romans or were at least not hostile. During this time the Romans conquered most of southern England. In AD. 51 the Brigantian queen went so far as to hand over to the Romans a defeated southern war leader who had come north seeking sanctuary. However peace did not last, the Brigantes split into pro and anti Roman factions, the anti faction being led by the queen’s husband! in AD. 69 the anti Roman faction got the upper hand. After this time there were several campaigns of conquest notably by Agricola who was Roman governor of Britain between AD 77 – 83 our road was probably built sometime during this period. The first fort at Ribchester was built around AD72 but was probably only permanently occupied during and after the Agricolan campaigns. These campaigns usually involved two armies moving simultaneously north on both sides of the Pennines, so east west communications such as provided by our road would have been very important so it is possible our road was built at this time.
Sources
Roman Roads Research Association http://romanroads.org becoming a member is highly recommended.
Margary, Ivan D. (1973); Roman Roads in Britain, John Baker, London
David Shotter 2002 Cerialis, Agricola and the Conquest of Northern Britain https://www.archaeologyuk.org/lahs/Cerialis.html
Barrie Tyrer