What it actually represents is a rath, the Irish term for a ringfort, the kind of enclosed farmstead that was built across Ireland in the early medieval period, roughly between 500 and 1000 AD. Thousands survive across the island, but each one carries its own peculiarities of construction and condition, and this one at Corkagh Beg is quietly instructive about how such places adapted to their surroundings.

The enclosure measures approximately 25 metres north to south and 27 metres east to west, making it a modest but complete example of the type. It is defined by a bank of earth and stone, between three and four and a half metres wide, that still stands around 0.9 metres high on its interior face. Unusually, no fosse, the external ditch that typically accompanies such banks and from which the material was originally dug, is visible at ground level; erosion has worn down the outer face of the bank along most of its circuit, and whatever depression once lay beyond it has long since been absorbed into the surrounding field. The builders also appear to have compensated for the natural slope of the hillside by raising the interior of the enclosure, levelling the ground within so that the area usable for daily life would have been reasonably flat. A gap of about 2.6 metres in the south-western section of the bank marks the original entrance, the point where people and livestock would have passed in and out, and which has remained readable in the landscape for over a thousand years.