Lower Min-y-Llyn is a motte, c.45m in diameter and 6.0m high, cut cut from a locally prominant north-east-south-west ridge above the floodplain of the Severn.

A ditch and counterscarp/forework cut across the ridge to the south-west, whilst it is thought possible that the present farm may overlie a former bailey to the north-east.

(source Os495card; SJ20SW2)
RCAHMW AP955003/41-3
J.Wiles 07.11.02