Cornovii (Cornwall) Dumnoniorum (present day Exeter), it is likely that he only listed Roman places, not purely native sites. Of these, there has been speculation that Voliba might be a place in Cornwall and Tamara is assumed to be on the River Tamar, the border between Cornwall and Devon. Ptolemy's list is supplemented by the problematical Ravenna Cosmography, which lists sixteen names before Isca Dumnoniorum (which is listed as "scadum namorum", showing some of the problems of this source) and which have therefore been assumed to be west of Exeter. Several have been identified as most likely in Devon, leaving "purocoronavis" (the
Isca Augusta Isca Augusta Isca, variously specified as Isca Augusta or Isca Silurum, was the site of a Roman legionary fortress and settlement or "vicus", the remains of which lie beneath parts of the present-day suburban village of Caerleon in the north of the city of Newport in South Wales. The site includes Caerleon Amphitheatre and is protected by Cadw. Headquarters of the Legion "II Augusta", which took part in the invasion under Emperor Claudius in AD 43, Isca is uniquely important for the study of the conquest, pacification and colonisation of Britannia by the Roman army. It was one of only