A circular enclosure roughly 21 metres across, it sits on a south-facing slope in pasture, its outline now traceable only as a low rise of about 14 centimetres along one arc and a slight scarp along another. Most people would walk straight across it without noticing anything at all.

Ringforts, known in Irish as raths, were the most common form of rural settlement in early medieval Ireland, typically consisting of a raised circular area enclosed by one or more earthen banks with an outer ditch, or fosse, and used as a farmstead or place of shelter. The one at Lisnaboy was already in a sorry state when Bowman recorded it in 1934, noting that about one-third of the circuit had been levelled by then, with the remaining bank still standing somewhere between six and ten feet high in places. The fosse had been infilled. The land at that point belonged to a M. Kearn. In the decades since, further deterioration has reduced the bank to the faint swelling visible today, a site that has lost almost all of its original physical presence to agricultural clearance and the slow work of time.