What survives above ground tells a quieter story: a shallow, grassed-over depression, roughly ten and a half metres long, running north to south. That faint crease in the turf is almost certainly the collapsed roof of a souterrain, an underground stone-lined passage or chamber built during the early medieval period, typically as a place of refuge, cool storage, or both. The structure has long since caved in, leaving only the outline of itself.

The ringfort it belongs to was itself a farmstead of sorts, a circular enclosure defined by earthen banks, common across Ireland from roughly the fifth to the twelfth centuries. Souterrains were frequently dug within such enclosures, their entrances concealed inside a dwelling. At Cloonymorris, the tradition of a cave attached to this particular fort has persisted long enough to be noted formally, even though nothing of the original structure is now accessible. The gap between what people have remembered and what the ground actually shows is part of what makes the site quietly interesting.