It is easy to miss. The bank that defines it rises barely a quarter of a metre above the surrounding pasture in most places, worn down in sections to little more than a scarp. Field boundaries cut across its western and southern edges, and the interior shows no visible features to the untrained eye. Yet the geometry holds: a near-perfect subcircular enclosure, measuring forty metres north to south and forty-two metres east to west, sitting at the highest point of the hill with views rolling out in every direction.

This is a rath, the most common type of early medieval settlement monument in Ireland. A rath was typically a farmstead enclosed by one or more earthen banks and ditches, its raised interior providing a degree of drainage as well as a degree of defence. At Ballycotteen, the slight rise at the centre of the interior is consistent with that pattern. Around the eastern side, traces of a berm, a flat ledge between an inner bank and an outer boundary, survive alongside an outer scarp about a metre high, suggesting the enclosure was originally more elaborately defined than what remains today. The site appeared on the Ordnance Survey six-inch maps of both 1840 and 1916, marked with hachuring that indicated an earthwork of some kind, though by 1996 it was catalogued more cautiously as an enclosure in the Record of Monuments and Places.

The hill's position between two streams was almost certainly deliberate. Such topographic choices were common among early medieval farmers, who used natural water features both practically and as soft boundaries around their landholdings. The monument at Ballycotteen retains enough of its original form to read as a coherent structure from ground level, even if the bank is intermittent and the outer earthworks fragmentary. The field boundaries that now slice across its edges are a reminder of how continuously the Irish landscape has been rearranged around, and sometimes through, its oldest surviving features.