Roman Roads with Small Side Ditches

Roman roads are frequently described as having ditches beside them, but these are usually large hollows of varying depth and width from which material has been scooped to form the agger of the roadway. The ditches discussed here are of quite a different type, and so far only four instances of them are known, though it is very probable that others exist. They are quite small, usually 3–7 ft. wide and a few inches deep; are cut in accurately straight lines parallel with the road and distant from it on each side by a space roughly equal to the width of the actual roadway; and are apparently found only in places where the road is crossing high and fairly level ground.