That word is almost certainly a surveyor's attempt to describe something rather more deliberate: a souterrain, an underground stone-lined passage or chamber built by early medieval communities, typically used for storage or refuge. The label has outlasted whatever local knowledge once explained it, and the feature itself has fared little better.

The site sits within a ringfort whose Irish name, Listoneen or Lios Tuainín, translates loosely as the ringfort of little Tuan. Ringforts, known in Irish as raths or lios, were enclosed farmsteads of the early medieval period, defined by one or more earthen banks and ditches. This one is univallate, meaning it has a single enclosing bank and fosse, the ditch dug to create that bank. The rath occupies a gently southward-sloping pastoral field and has been considerably levelled over the centuries, to the point where its interior now sits at roughly the same height as the surrounding land. What survives is a subdued, sub-circular raised area. In its north-eastern sector lies an oblong mound measuring approximately 2.6 metres by 16 metres internally, and it is this mound that is most likely the collapsed or filled remains of the souterrain once marked on that Victorian map. Just to the east of the rath proper, a sub-rectangular raised area, around 18 metres by 25 metres and still standing some 1.4 metres high, suggests a connected enclosure, possibly an outwork or annexed space associated with the original fort, though its precise function is uncertain. The North Kerry Archaeological Survey, compiled by C. Toal and published in 1995, recorded these features and noted their probable relationship, without being able to resolve all the questions the landscape quietly poses.