No hollow in the ground, no tell-tale depression, no visible sign that anything lies below. It has, to use the archaeological shorthand, no visible surface trace, which is a quiet way of saying it has effectively vanished from the landscape while remaining, technically, present in it.

A souterrain is a man-made underground structure, typically stone-lined or earthen, associated with early medieval ringforts and used variously for storage, refuge, or both. This particular example sits within a ringfort at Loughane, and what little is known of its dimensions comes from a discovery recorded by Caulfield in 1866. The chamber he found was modest even by souterrain standards, roughly two feet eleven inches high and two feet wide at the point where it formed an arch. Inside the debris he noted charcoal and small fragments of bone, the kind of material that hints at occupation or activity without being specific enough to tell a fuller story. Whether the bones were animal or human, whether the charcoal came from a hearth or something more incidental, the record does not say. What the dimensions do convey is a space barely large enough to crouch in, low and close, the sort of place that would press in on a person in complete darkness.