Caerau is an irregular, generally sub-rectangular earthwork enclosure, about 80m east-west by 60m, set upon a ridge-top summit, that shows traces of a bank and ditch on the north and east, with scarps on the south, having an entrance through the north-east angle; the western part of the enclosure has been obscurred, cultivation marks being apparent over this area (J.Wiles 29.11.04).

This is a damaged small hillfort which nonetheless occupies a very strong position on a rounded hilltop, commanding extensive views across the Rheidol Valley to the south, and defended by naturally steep slopes on the north, west and south sides. The hillfort appears to have been univallate with a gateway on the north-east side, flanked by an outer bank. The Ordnance Survey noted that an artificial scarp can be traced for about 60m west of the entrance, perhaps showing the northern extents of the fort. The rampart on the east side has been considerably reduced to c.0.5m. Ceredigion Archaeological Survey noted traces of house platforms within (Hogg and Davies, Cardiganshire County History 1994, 265). A second hillfort was discovered during RCAHMW aerial reconnaissance in 1999 on rounded summit to north (Alltfadog South, NPRN 301885).

T. Driver, 15 June 2007.