Tucked into the centre of a ringfort, a partially collapsed underground chamber sits quietly in what was, for its original inhabitants, a place of concealment or storage, perhaps both. It is small, just over three metres long and not quite one and a half metres wide, running on a north-west to south-east axis, and what survives of it tells you something about how it was made.

The structure is a souterrain, a type of dry-stone underground passage or chamber built during the early medieval period in Ireland, typically associated with ringforts and used variously for food storage, refuge, or as a place to hide valuables. This example at Quinaltagh retains sections of its corbelled side-walls, meaning the stones were laid in overlapping courses, each projecting slightly inward, to carry the weight of whatever covered the chamber above. No lintels, the flat capstones that would have roofed it, survive, and part of the structure has collapsed, leaving the interior partially open to the sky. That collapse is itself revealing: without its covering stones, a souterrain that might otherwise pass entirely unnoticed becomes legible, its internal arrangement suddenly visible from above. A reference recorded by Neary in 1914 suggests the site had already attracted some antiquarian attention over a century ago, though the chamber has changed little in the intervening years beyond further weathering and settling.