A souterrain, an artificial stone-lined passage or chamber built during the early medieval period, typically for storage or refuge, was recorded on the first edition Ordnance Survey six-inch map of 1841 as a "cave" sitting within the interior of a ringfort. By the time anyone looked carefully at the ground in 1985, there was nothing visible left to find.

The 1841 mapping places the feature just north of centre within the ringfort, a type of enclosed farmstead common across early medieval Ireland, usually defined by one or more earthen banks and ditches. The label "cave" was a fairly standard shorthand used by early OS surveyors when they encountered the tell-tale depression or opening of a souterrain without necessarily understanding its archaeology. That the souterrain sat inside a ringfort is not unusual; the two features frequently occur together, with the underground passage likely serving the inhabitants of the enclosed settlement above. What is unusual here is the degree to which the site has disappeared from the surface. When surveyed in 1985, no trace of the souterrain could be detected, leaving only the cartographic record as evidence that it was ever there at all.