Caerleon is a site of considerable archaeological importance, being the location of a Roman legionary fortress or Castra (it was the headquarters for Legio II Augusta from about 75 to 300 AD) and an Iron Age hill fort. The name Caerleon is derived from the Welsh for "fortress of the legion"; the Romans themselves called it Isca. Substantial excavated Roman remains can be seen, including the military amphitheatre, thermae (baths) and barracks occupied by the Roman Legion. According to Gildas (followed by Bede), Roman Caerleon was the site of two early Christian martyrdoms, those of Julius and Aaron. Recent finds suggest Roman occupation of some kind as late as AD 380.[2] Roman remains have also been discovered at The Mynde, itself a distinctive historical site.