What was once a subcircular earthwork, roughly 34.5 metres across on its north-west to south-east axis and 28 metres on its north-east to south-west axis, has been partially consumed by quarrying and then further altered by the construction of a reservoir within its own interior. What remains is a scarp, the slope of a cut or eroded bank, tracing an arc from the north-north-east around to the east, and from the south-east back through the west to the north. The original shape of the enclosure can still be read in that surviving curve, even if its substance has been largely removed.

Enclosures of this kind are broadly related to the ringfort tradition that characterised rural settlement across early medieval Ireland, roughly the fifth to twelfth centuries. Ringforts, typically circular banks enclosing a homestead or farmstead, are among the most common archaeological monuments on the Irish landscape, and the presence of one a mere 70 metres to the south-east at Radullaan suggests this hillock sat within a wider pattern of activity. Whether the enclosure here served a domestic, agricultural, or ceremonial purpose is not recorded, and its poor state of preservation makes interpretation difficult. The quarrying that damaged it may have been relatively recent in historical terms, the stone of the scarp and bank being a convenient local resource, and the addition of a reservoir inside what was once a defined and perhaps significant space is a quietly striking combination of the ancient and the utilitarian.