The main feature is a roughly rectangular enclosure measuring approximately 46 metres north to south and 34 metres east to west, defined by substantial earthen scarps. The western, northern and eastern boundaries are marked by impressive scarps nearly 5 metres wide and just over a metre high, whilst the southern edge has a more modest scarp about half that height. Along the eastern side, and continuing somewhat along the south, runs a defensive fosse or ditch, originally around 6.5 metres wide and still visible at depths of 30 to 35 centimetres.

Within this enclosure, positioned off-centre towards the west, stand the ruins of Ballinaclogh Castle itself, marked on Ordnance Survey maps since the 19th century. Various irregular features are scattered across the interior, including what appears to be a medieval drainage system; a possible leat running east to west for about 26 metres, likely designed to carry waste from the castle’s garderobe and surface water runoff away from the structure. This practical piece of engineering would have been essential for maintaining sanitary conditions within the fortification.

The defences extend beyond the main enclosure, with an outer defensive element curving around the western and northern sides, creating additional rectangular spaces between the inner and outer boundaries. These layered defences form a larger complex measuring roughly 94 by 64 metres overall. Traces of what may have been an annexe can still be detected as a low terrace adjoining the western side at its southern end, though time has rendered these features barely visible. Together, these earthworks represent a sophisticated defensive arrangement typical of Irish fortified sites, where multiple lines of defence and practical drainage solutions were essential for both security and daily life.