Caerleon is a town famous for its history and archaeological importance. `Caerleon? is taken from the Welsh for `fortress of the legion?, having been the site of one of the three Roman Legionary Fortresses in Britain (NPRN 95647). However the location, on the bank of the River Usk, was already strategically important prior to the arrival of the Romans, as attested by its Iron-Age Hill Fort (NPRN 93396) which remained in consistent use from the fifth century BC into the later Roman period. There is much surviving evidence of Roman occupation in the region, including the amphitheatre and baths (NPRN 310464) and the only visible excavated Roman legionary barracks in Britain (NPRN 402679).
A motte-and-bailey castle was constructed at Caerleon following the Norman Conquest, and although no charter survives from the period, it appears evident that by 1171 the town was an important market and borough. In 1217 the castle and borough were seized by William Marshall, following which the castle was rebuilt in stone (NPRN 307940). Caerleon was, for several centuries the major port along the River Usk, and boasted an impressive seventeenth century Market Hall (NPRN 408591), however it was later overshadowed by the development of Newport. Following the establishment of tinplate mines nearby, Caerleon expanded to almost meet the neighbouring town.

K Steele, RCAHMW, 30 December 2008