The enclosure measures approximately 32 metres north to south and 30.4 metres east to west, dimensions that place it firmly in the range of a ringfort, the kind of enclosed settlement that was common across Ireland from the early medieval period onward. What makes its position worth noting is the landform itself: a drumlin is a smooth, elongated hill shaped by glacial action, and whoever chose this spot carved their enclosure into the scooped-out western end of one, using the steep sides of the ridge as a natural part of the design.

The earthwork is poorly preserved, which means the bank that once defined it survives only in parts. Along the eastern half the boundary is readable as a scarp, a sharp drop in the ground surface rather than an upstanding wall or bank, while elsewhere a low earthen bank marks the perimeter. McCaffrey recorded the site in 1952, cataloguing it among a broader survey of such features in the area. A round house site lies roughly 150 metres to the north-west, suggesting that this corner of Ballylin was once a focus of settlement activity, with the enclosure and the round house perhaps functioning within the same landscape, if not the same community or period.