Castell-prin is a sub-rectangular enclosure measuring some 70m east by west by 34m. It rests on steep, rocky slopes on the north, but is elsewhere defined by a bank, ditch and counterscarp bank, with a south-south-west facing, inturned entrance.
There are ruins within of a stone-founded structure, 4m by 3m.
OS record card ST49SW34.
RCAHMW air photos: 945058/61; 955222/53.