There is nothing to see at the surface, no marker, no hollow in the ground, no obvious disturbance in the pasture. The structure exists more as a fact on record than as anything a visitor could encounter, which makes it a peculiar kind of archaeological presence.

Souterrains are stone- or earth-cut underground chambers, typically associated with early medieval settlement in Ireland, thought to have been used for cold storage, refuge, or both. The example at Coom was earth-cut rather than stone-lined, which places it among the less elaborate but nonetheless purposeful examples of this type of construction. It came to light in the 1930s and was recorded as comprising three chambers connected by a narrow passage, a modest but coherent arrangement suggesting deliberate design rather than accidental collapse or natural formation. Local knowledge gathered as recently as 2005 indicated that the souterrain extends northward from beneath the road and its verge into the adjoining pasture field, meaning the modern road itself was laid, at some point, directly over part of this much older structure. The chambers have since been closed up, and the ground above them gives no sign of what lies beneath.