The one at Cashla, in County Galway, breaks from that pattern. It is subrectangular, a shape unusual enough to make even a passing archaeologist stop and look twice, and it is large: roughly 160 metres on its longer axis and 120 metres across. That scale, combined with its irregular geometry, sets it apart from the more common domestic enclosures of early medieval Ireland.

The site sits in undulating grassland and is, by any honest account, poorly preserved. What defined it originally was a bank of earth and stone accompanied by an external fosse, a defensive ditch running around the outside of the enclosure. The fosse survives from the south around through the west to the north, and is at its clearest on the northern side, where it retains a flat-bottomed profile. Much of the bank itself has been obscured by a later field wall built directly over it, running from the south-east through the west and up to the north, which makes reading the original outline a matter of careful attention. Inside the northern half of the enclosure, a series of banks survive, similar in size and construction to the outer bank, which may represent internal divisions, perhaps separate areas for animals, storage, or different household functions within what was once a working settlement. In the south-western quadrant there is a souterrain, an underground stone-lined passage or chamber of the kind commonly associated with early medieval ringforts, used variously for storage, refuge, or both.

The layering of the site, an early medieval enclosure gradually overtaken by later agricultural boundaries, is typical of how such places survive in the Irish landscape, recognisable but altered, their original purpose half-buried under centuries of ordinary farming life.