A large, 3.8ha, Roman fort, known from parchmarks and the exceptionally clear results of geophysical survey. It is part of the larger Llanfor Roman military complex (NPRN 95489) and is a rectangular enclosure with rounded corners, roughly 200m east-north-east to west-south-west by 185m. It is defined by traces of a rampart fronted by triple ditches.

The internal buildings are known in considerable detail. These include twenty-two barrack blocks, which could have accommodated 1,760 soldiers. The fort faced east-north-east, where there are indications of an approach road lined with buildings. There are similar traces to the north-east. The northern fort ditches overlap that of a large temporary camp (NPRN 308244) which may be a later feature. There is little dating evidence, but it is assumed that it pre-dates the Flavian fort at Caer Gai at the opposite end of Lake Bala. A very early Flavian date is also suggesed by the few finds from the site and the large size and densely packed interior suggest association with an active force on campaign.

Sources: St Joseph in the Journal of Roman Studies 67 (1977), 149-50 fig 15
Crew & Crew in Archaeology in Wales 37 (1997), 13-20
Hopewell in Britannia 36 (2005), 247-53

RCAHMW, November 2010.