It was not a cave. What they recorded was a souterrain, an artificially constructed underground passage or chamber built during the early medieval period, typically associated with nearby settlements and used variously for storage, refuge, or both. The label stuck on paper for generations, a small cartographic misidentification that quietly obscures what is actually a more deliberate and considered piece of construction.

The souterrain sits at the centre of a ringfort, the circular enclosed settlements that were the dominant form of rural habitation in Ireland from roughly the sixth to the twelfth century. Ringforts were typically defined by one or more earthen banks and ditches, and souterrains built within them were a fairly common feature, though no less interesting for that. What makes the Gneeves site slightly unusual is that there is a second souterrain as well, positioned at the northern perimeter of the same fort. Two souterrains within a single enclosure suggests a site of some complexity, perhaps one serving a different function or period of use than the other, though the specifics remain unclear. The site has not been excavated in any documented way, and at the time the archaeological inventory was compiled, permission to inspect it was refused, leaving its interior condition and full extent unrecorded.