The earthwork at Lackaduv sits on a south-facing slope, its interior dipping gently toward the north-east and interrupted by rock outcrops, as though the ground itself could not quite decide between natural formation and human intention. That ambiguity is part of its character. Where a constructed earthen bank defines the enclosure from the south-east around to the north-north-west, the natural scarp of the hillside takes over, meaning whoever built this place was working with the landscape rather than imposing upon it.

Ringforts, known in Irish as raths when they are earthen rather than stone, were the standard enclosed farmstead of early medieval Ireland, typically dating from roughly the fifth to the twelfth century. They housed a family and their livestock, and their enclosing banks were as much a statement of status as a practical barrier. The Lackaduv example measures approximately 38 metres north to south and 32 metres east to west, making it a modest but respectable size. When surveyors recorded it for the Ordnance Survey's six-inch map of 1842, they rendered it as a hachured circular enclosure of around 30 metres in diameter; by the time later OS maps were produced in 1903 and 1940, the depiction had shifted to a hachured oval raised area, a small but telling change that reflects either greater precision or slight alterations to the visible earthworks over time. Perhaps the most intriguing feature is a possible souterrain in the southern half of the interior. A souterrain is an underground passage or chamber, usually stone-lined, associated with ringforts and thought to have served for storage, refuge, or both. Whether the one at Lackaduv is intact or partially collapsed is not recorded, but its presence would not be unusual in a site of this type.