The oval-shaped internal mound, which measures approximately 30m by 48m across the top, is bounded by a steep-sided rock-cut ditch. The ditch is surrounded by a steep-sided rampart between 10m and 15m wide, which has been partly formed by deliberately accentuating the natural fall at the end of the ridge. To the north east, the rampart is set further away from the mound thereby increasing the width of the ditch. This part of the defensive circuit has been modified by stone quarrying in the 19th and 20th centuries. A deep cut has been made through the bank, part of the ditch has been cut away and quarry spoil has been dumped over the outer defences to the north. Next to the outer side of the north eastern part of the rampart there are additional quarry hollows and spoil heaps, which are not included in the scheduling. To the north, corresponding with the gently rising spine of the ridge, is a break through the rampart, about 3.5m wide, which appears to mark the position of the original entrance passage to the interior of the castle. The positions of structures within the interior are marked by embanked wall footings, piles of collapsed masonry and level building platforms. A mass of collapsed stonework also lies within the ditch, particularly to the south and the north west. In 1963 a small-scale archaeological excavation was conducted in order to provide information about the structural history of the site. From this investigation it would appear that originally the interior of the ringwork had been defined by an inner rampart and that the contemporary structures were built of wood. At a later date a stone round tower or keep was built at the southern end of the interior of the ringwork. It measured about 6m in diameter internally, with a wall roughly 2.5m thick. A stone curtain wall, about 2m wide, was then constructed around the interior, abutting the tower and cutting into the remains of the earlier inner rampart. A D-shaped stone tower was added to eastern and western sides of the curtain wall, and a twin D-shaped towered gateway, also of stone, was constructed at the northern end of the interior. Following a major structural collapse, the gateway was rebuilt to form an enlarged gatehouse, and the adjoining part of the curtain wall to the west was also strengthened. A quantity of iron nails and animal bones, together with an iron arrowhead, was found in a deposit predating the curtain wall, and within the round tower large burnt timbers were discovered. It is considered that the ringwork was built in the late 11th or the early 12th century and would have been vital in securing the lordship boundary. The subsequent stone-built enclosure castle, comprising the round tower, curtain wall, D-shaped side and gate towers, is believed to have been built in the 13th century, during which time it served as a border outpost for the lordship. The rebuilding of the gateway and an adjoining portion of the curtain wall, probably in the later 13th century, emphasises the castle's continuing role as an important border fortification at this time. (Scheduling Report)
The modern name, in use locally, is Castle Cefn Fron. Paul Remfry informs Gatehouse this is the probably site of Castle Hithoet mentioned in contemporary documents.