Nanstallon in 1965 by Aileen Fox and Professor W. L. D. 'Bill' Ravenhill. Until recently (2007) it was the second Roman fort in Cornwall but following a geophysical survey another Roman fort has been found away near Restormel Castle. Constructed c. AD 55–60, Nanstallon fort is situated in mid Cornwall near the Fowey-Camel trade and communication route. Nanstallon was probably a forward operating base and was strategically well-placed for a Roman presence to be felt. However, the Roman Legion at Exeter was withdrawn c. AD 75 and with no Roman town west of Isca Dumnoniorum Cornwall settled down to four centuries
Isca Augusta three permanent legionary fortresses in later Roman Britain and, unlike the other sites at Chester and York, its archaeological remains lie relatively undisturbed beneath fields and the town of Caerleon and provide a unique opportunity to study the Roman legions in Britain. Excavations continue to unearth new discoveries on the extent and nature of the site. One of the most exciting discoveries is a complex of very large monumental buildings outside the fortress between the River Usk and the amphitheatre. This new area of the "canabae" was previously completely unknown. The Brythonic name "Isca" means "water" and refers to the