Colwyn Castle is mentioned in documentary sources in 1144 (and possibly again in 1315) and partly overlies the site of a Roman fort (NPRN 401567). The surviving remains include a ditched and counterscarped circular enclosure, c.65m in diameter set within, and at the junction of, two contiguous subrectangular ditched and banked enclosures approximately 280m by 160m. The castle is thought to have been reconstructed in stone in about 1240 and to have been demolished in 1629.

(source Os495card; SO15SW6)

J.Wiles, RCAHMW, 18 April 2004