At Knockaninane, within the earthwork remains of a rath, a souterrain, which is an underground stone-built passage or chamber used in early medieval Ireland for storage or refuge, lies blocked and covered, its interior unknown. A depression in the southern half of the enclosure hints that at least one chamber may have already collapsed inward, leaving only a subtle hollow in the ground to suggest what lies beneath.

The rath itself, a roughly circular earthen enclosure typical of early medieval settlement in Ireland, provides the context for this buried feature. Souterrains were commonly dug within such enclosures, and the presence of a hut site nearby within the same rath suggests a settlement of some activity, even if its precise date and character remain unexcavated. The landowner's account of the blocked and flagged entrance is the closest thing to a description of what survives above ground. Whether the structure beneath is intact, partially collapsed, or entirely filled, no investigation appears to have been carried out.

The site presents itself as little more than a gentle dip in a grassy enclosure, easy to misread as nothing at all. The rath's inner bank is still visible to the south, and the spatial relationship between the depression, that bank, and the hut site to the north is the clearest guide to where the souterrain may once have opened. There is nothing to enter and nothing to excavate without permission, but the arrangement of these features on the ground, a flagged mouth, a sunken floor, a curved earthwork, tells a quiet story about the way people organised their lives and their secrets in early medieval Kerry.