The circular earthwork here is a rath, the Irish term for a ringfort, which was the standard form of rural settlement in Ireland from roughly the fifth to the twelfth centuries. Typically consisting of a raised bank of earth enclosing a circular area where a family and their livestock would have lived, raths were once so numerous across the Irish landscape that several hundred thousand are thought to have existed. At Slieveroe, agricultural improvement has done its best to erase the evidence, yet the site has not entirely disappeared.

The ringfort sits in marshy ground on the western side of a stream, a location that would have offered both a water source and a degree of natural protection. A 1934 Ordnance Survey six-inch map still shows it as a clear circular enclosure, giving some indication of how recently the land was in better condition. By the time field investigators recorded it, the bank had been levelled almost flat, surviving only as a low rise that traces a circular area roughly 58 metres in diameter. The field had been reclaimed and subjected to deep ploughing, and a field fence along with a deep drainage ditch now cuts straight across the interior on an east to west axis. What remains most legible is the soil itself: the ground within the former enclosure is noticeably darker than the soil of the surrounding bank, a contrast that likely reflects centuries of accumulated organic material from human and animal activity within the enclosed space.