What looks at first like a lumpy, unremarkable platform turns out to be a carefully engineered enclosure, roughly oval in plan and measuring some 35 metres north to south by 51 metres east to west, surrounded by a system of earthen banks and fosses, the term for the broad ditches dug alongside defensive or enclosing earthworks. A causeway crosses the works at the north-north-west, suggesting a deliberate, formalised point of entry. The southern side has suffered badly at the hands of the Finglas, which has carved a high meander scarp into it over the centuries, eating away at the structure and carrying off much of what once defined that edge.

The engineering of what remains is still legible. The platform itself sits up to two metres above the surrounding ground level at the west, and the central fosse that defines it reaches an average of three metres below the platform surface, with a flat bottom and a basal width varying between two and a half and five metres. To the south-west and running around to the north-east, a broad external bank survives, up to seven metres wide at its crest and best preserved on the western side, where a smaller bank edges both sides of the top. Built into the outer face of this western bank is a small lime kiln, a modest post-medieval structure used for burning limestone to produce quicklime for agricultural or building use. Its presence here is a reminder that long after the enclosure lost whatever function it originally served, people were still making practical use of the ground it occupied. A second, outer bank is faintly traceable to the south-west, separated from the inner one by a shallow fosse roughly two metres wide. Part of the northern bank has been absorbed into a field trackway, its outer edge obscured by a later field boundary.