|N (6) to Gelligaer (Mid Glamorgan)
S (8) to Cardiff (South Glamorgan)
|ST153872||c.360 x 350 ft
(c.110 x 107 m)
The north-western corner angle of this Roman auxiliary fort was discovered by accident in 1963 during excavations conducted by J.M Lewis upon the northern outworks of Caerphilly Castle. A large earthwork constructed during the English Civil War (c.A.D.1645) lies wholly within the confines of the Roman enlosure and occupies about half of its interior area.
The Roman fort occupied much of the area now contained within the circuit of Crescent Road, Nantgarw Road, the western end of North Lake, and the north-western defences of the Norman Castle. The limited investigations conducted in 1963 located the north-western angle and short lengths of the north-west and north-east defences, and the position of the north-eastern angle may be deduced, which gives an east-west dimension of about 360 feet (c.110 m). The remnants of the fort's south-eastern defences may be retained within an enclosure lying just 130 feet (c.40 m) outside the castle wall. If this is the case, then the north-south dimension of the fort may have been around 350 feet (c.107 m) which would have given an almost square outline with an occupation area of not quite 3 acres (c.1.2 ha).
The 1963 excavations defined the nature of the Roman defences; they comprised a bank of turf and clay set upon a base of cobblestones about 24 feet wide (c.7.3 m) and fronted by a timber revetment, before this rampart were two V-shaped ditches spaced about 5 feet apart (c.1.5 m), each measuring about 9¼ feet wide and 3 feet deep (c2.8 x 0.9 m); there was no discernable berm between the face of the rampart and the inner ditch. Finds include Samian ware dated c.A.D.75-100, coarse pottery ranging from early Flavian to late Antonine (c.75-160), fragments of glass bottles dating to the late-1st or early-2nd century, a lead weight and other assorted fragments of lead.
"The excavator considered the fort to have been established ca. 75 and occupied at least at least until the middle of the 2nd century." (Glamorgan Inventory, p.95)
There is a Roman temporary marching camp 6½ miles to the west at Pen-y-Coedcae (ST0687).