NGRef: SN8206
OSMap: LR160
Type: Fortlet

Roads
Sarn Helen: NE (3.5) to Coelbren (West Glamorgan)
Sarn Helen: SW (7.5) to Nidvm (Neath, West Glamorgan)

The Roman Fortlet on Hirfynydd Ridge

N.G.REF DIMENSIONS AREA
SN828067 77 x 75½ ft
(c.23.5 x 23 m)
c.0.1 acres
(c.0.05 ha)

This site lies on the 'Sarn Helen' Roman road about 3½ miles (c.5.6 km) south-west of the fort at Coelbren. The fortlet is almost square with sharp corner-angles, measuring 77 feet by 75½ feet (c.23.5 x 23 m) across the rampart crests, thus enclosing an area of only one-tenth of an acre (c.0.05 ha). The defences consisted of a single rampart and ditch, measuring 8 feet (c.2.4 m) and 5 feet (c.1.5 m) wide respectively; there is a single entrance gap, 10 feet (c.3 m) wide, in the centre of the south-eastern side, facing the Roman road.

See: Air Reconnaissance in Britain, 1958-1960 by J.K. St. Joseph in J.R.S. li (1961) p.126;