The one that once occupied the summit of a high drumlin hill at Corbeagh in County Cavan has been levelled, leaving behind little more than a description of what was there before it disappeared. That description, recorded by the Office of Public Works in 1969, is precise enough to conjure the place: a raised circular area roughly 35 metres in internal diameter, ringed by two substantial earthen banks, with wide, deep outer fosses, or ditches, that were partly waterlogged. The entrance, where it could still be read in the landscape, faced south-south-east.

Ringforts, known in Irish as raths when constructed from earth and bank rather than stone, are among the most common archaeological monument types in Ireland, with tens of thousands once scattered across the countryside. They served primarily as enclosed farmsteads during the early medieval period, roughly 500 to 1000 AD, and their double-bank construction, as at Corbeagh, generally indicates a site of some local status or defensive ambition. The choice of a drumlin summit is telling too. Drumlins, the smooth elongated hills shaped by glacial movement that cluster so thickly across Cavan and the wider Ulster borderlands, offer natural elevation and visibility, making them attractive positions for anyone wishing to survey the surrounding terrain. The waterlogged condition of the outer fosses, even when surveyed in 1969, suggests the site retained some of its original character into the modern era, before subsequent levelling erased what centuries had preserved.