Near the crest of a broad east-facing hill at Cush of Grange in County Waterford, there is an earthen enclosure that manages to be quietly puzzling in several ways at once. It has no visible entrance. Whatever purpose it served, nobody walked in or out through a gap that survives today, and the ground inside gives nothing away, remaining a subcircular spread of grass roughly 28 metres east to west and 24 metres north to south. The defining bank, up to 5.5 metres wide and nearly two metres high on its northern side, diminishes around the southern and eastern arcs to little more than a low scarp. Outside it, faint traces of a fosse, a defensive ditch, can still be made out, though shallow at around 0.2 metres deep and inconsistent in width.

What makes the site stranger still is a detail preserved on the 1840 edition of the Ordnance Survey six-inch map, which marks a 'cave' in the vicinity. In Irish archaeological contexts, such a marking often signals a souterrain, an underground stone-lined passage typically associated with early medieval settlements, sometimes used for storage, sometimes for refuge. But no physical evidence of one has been found here, and there is apparently no local tradition of its existence either. The map annotation remains unexplained, a cartographic footnote that raises more questions than it answers. Embanked enclosures of this type are known across Ireland, though their precise functions varied considerably, ranging from settlement boundaries to ritual or agricultural use, and without excavation this one is unlikely to give up a definitive answer.