Royal Commission aerial reconnaissance on 19th July 2018, during the 2018 drought, identified part of a previously unrecorded Roman marching camp adjacent to a Roman fort (NPRN 423858) in Gwernyfed Park, Three Cocks. The 64m long north-east side, with the NW and NE rounded corners, of the probable marching camp is visible sited approximately 23m away from the south-west corner of the Roman fort, suggesting a close association between the initial defence of the site and the subsequent construction of the fort. No further traces of the camp can be seen to the south-west; however the presence of a minor stream some 90m south-west of the visible line of camp rampart may suggest a maximum extent of this camp. Its siting is similar to the Cefn-Brynich Roman camp (associated with the fort, NPRN 419242; see Davies and Driver 2015) or construction camp which is sited only 25m west of the defences of the fort, and of which only the north-west corner is visible.

T. Driver, RCAHMW, Jan 2019.