Amid the open grassland of the Curragh, one of Ireland's most unusual landscapes, a circular earthwork sits quietly in the plain, its geometry precise enough to read clearly from ground level even after centuries of exposure. The enclosed area measures thirty-one metres across, ringed by a well-defined fosse, the term for a defensive or boundary ditch cut into the earth, with a low outer bank beyond it. Between the fosse and that bank, a slight berm, a narrow shelf of ground left standing between the two features, remains visible along the north-east to south-south-east arc, giving the whole monument an overall diameter of around fifty metres.

This kind of monument is known as a rath, a roughly circular enclosure defined by earthen banks and ditches, typically associated with early medieval settlement in Ireland, though the Curragh has been a contested and layered landscape for far longer than any single monument type suggests. The site was recorded and discussed by Seán P. Ó Ríordáin in 1950, catalogued as Site U in his survey work, where a scaled east-west section was also published. Some disturbance at the northern end is noted, likely the result of more recent activity rather than ancient remodelling, though it has not significantly obscured the overall form.