The rath at Dunmoran, Co. Sligo is a different proposition. Here, a circular platform some 28 metres across sits atop a steep-sided earthen mound that rises to 5 metres, giving the whole structure an unusual, almost fortress-like elevation for a monument of this type. A ringfort, or rath, was typically a farmstead enclosed by earthen banks, used during the early medieval period roughly between the fifth and twelfth centuries. The version at Dunmoran pushes that formula to something considerably more imposing.

The engineering detail is worth pausing over. The platform itself is ringed by a bank of earth and stone, and between that bank and the edge of the platform sits a narrow berm, a flat ledge, between one and a half and two and a half metres wide. Below, at the foot of the mound, runs a fosse, the ditch that would have reinforced the site's defensive character, four metres across and over a metre deep, fronted by a substantial outer bank nearly six metres wide. Access was managed by a ramped causeway at the south-southeast, crossing the fosse through an entrance gap four metres wide. The southern portion of the fosse and its outer bank has been levelled over time, and the outer bank to the north and east has been absorbed into a later field boundary, the kind of quiet erasure that happens when farmland quietly swallows older structures across centuries. Local tradition holds that a souterrain, an underground stone-lined passage often associated with storage or refuge, lies within the site, and a disused field system survives a short distance to the west, suggesting a broader pattern of early settlement in the immediate area.