There is no hollow in the ground, no tell-tale depression, no stone lintel poking through the grass to give it away. The surface offers nothing at all.

A souterrain is an underground passage or chamber, typically built during the early medieval period in Ireland, constructed from stone and used variously for storage, refuge, or as an adjunct to a nearby settlement. This one sits in the south-western quadrant of a ringfort or enclosure, the kind of enclosed farmstead that was the standard unit of rural life in Ireland between roughly the fifth and twelfth centuries. The pairing of souterrain and enclosure is entirely typical; what is less typical is the completeness with which this example has disappeared below the surface. It was recorded as having no visible surface trace, meaning that its existence is known only through prior documentation rather than anything a passing observer could detect.