The Making of A Roman Road

  • 11 Jan 2024
  • Old Roads
  • Back

Roman roads were once thought to be of two kinds, Streets which were paved with granite sets, and Ways which were unpaved, but archaelogical evidence does not bear this out. They were however, all constructed of several layers which raised the road surface well above the level of the surrounding land, forming a causeway known as an agger.

The usual road for the passage of two vehicles without collision had a width of about 14 feet, but the agger would be considerably wider, making what we would call now a 'hard shoulder' on each side.                         On either side of the agger, a ditch was cut which would provide material for the construction of the agger, and also provide drainage along the edge of the road. The base of the agger was well rammed in, with a layer of small stones and gravel, sometimes left dry, or with mortar poured in. Next a layer of broken stones to two parts of lime, followed by a layer of lower grade material, usually gravel, clay and lime, with any local debris such as iron-slag. Finally, the wearing pavement surface consisting of fitted stones like sets or flagstones, or on lesser roads, a surface of gravel and lime concrete. Great care was taken to keep the water out of the road by cambering the surface and efficient drainage.

Most Roman Roads were provided with milestones, the standard mile was of 1,000 paces, but since the Roman pace was that of a man running rather than walking, it was five feet long, thus the Roman mile was some 93 yards shorter.

Today, Britain as approximately  2000 miles of Roman roads left today (Jan 2024).