A rectangular enclosure, about 100m north-east to south-west by 70m, set on the summit of a natural hillock, above the flood plain of the Afon Vyrnwy: the north-west and north-east sides rest on steep slopes, the enclosure being defined elsewhere by a double bank with a medial ditch: thought to have been the caput of the manor of Dynas, mentioned in the 14th century: 'tooled stonework' has been noted within the enclosure.
