From The Devil's Causeway by Walter Elliot
On the top of Ayton Hill at 94643 59692, there is an enclosure which was noted in 1776 but not found in The Archaeological Sites and Monuments of the Berwickshire District 1980.
It is a large enclosure with the ditch on the inside suggesting it was for keeping stock in rather than anything out. There is a square enclosure beside it which has the size and shape of a Roman fortlet (F2) and watch tower/signal station (W3) 50m to the east. From this tower, it is possible to see at least 15kms in all directions and even the shore of Fife on a clear day.
Some of these structures may not be Roman but they would fit nicely into the road pattern. From Ayton Hill, the joint Roman/Post road went down to a bridge on the downstream side of the old Ayton Church until a period between 1771 and 1794. After that the Post Road was re-routed to the new bridge upstream of the Church.
On the flat haughs before the bridges, there is a complex of three Roman forts. From the edge of the road, there is a side road which leads to Eyemouth suggesting that there was a Roman harbour.
To navigate to the site you can download a gpx file below, for instructions see the Visiting Sites page.