Originally raised in the late eleventh century and re-fortified in stone between 1277 and 1282, Builth Castle was once described as "a fair castel of the Kinges". It was probably demolished in the late sixteenth century but the surviving earthworks now appear both complex and powerful. They are 140m by 151m overall.
(source OS495 card; SO05SW4)
J.Wiles, RCAHMW, 31 July 2002