Remains of a Roman auxiliary fort situated on the north end of a locally prominent ridge to the west of the Afon Ely were first identified in 1999. The fort was built during the early Flavian military consolidation of South Wales and would have been occupied between AD 70 and AD 85 by between 500 and 1000 men. It was probably superceded by a small fortlet associated with extensive iron production in the immediate vicinity, but this appears to have abandoned early in the second century, though iron production continued into the mid third.

The bi-vallate fort itself measures 128m by 122m. The ditches at the north and west gates at least were linked to form 'parrot's beaks'. Internal detail has not been identified although some indication of barracks came from the geophysical survey between 2000 and 2004. The fortlet was also identified by geophysical survey and measures 100m by 60m and is positioned symetrically within the earlier fort.

Source: Cadw scheduling description.

F. Foster, RCAHMW, 1 December 2005