Isca Silurum

A Roman legionary fortress in South Wales. It was one of the only permanent legionary fortresses in Roman Britain, and served as a major strategic center in the region, also known as Isca. 
Isca was founded in 74 or 75 A.D. during the final campaigns by Governor Sextus Julius Frontinus against the fierce native tribes of western Britain, notably the Silures in South Wales, who had resisted the Romans’ advance for over a generation. Isca became the headquarters of the Legion II Augusta based in the large fortress of a typical legionary "playing-card" shape, and it was built initially with an earth bank and timber palisade. It remained their headquarters until at least 300 AD. The interior was fitted out with the usual array of military buildings: a headquarters building, legate's residence, tribunes' houses, hospital, large bath house, workshops, barrack blocks, granaries and an unusually large amphitheater. 
Isca Silurum, or Isca Augusta later became the castle-city Caerleon in Wales, the seat of King Arthur's Court of the Round Table.
Also: Cair Legeion guar Uisc or Fortress of the Legion, that is City of Legions
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