A souterrain, to use the technical term, is an artificially constructed underground chamber or tunnel, typically lined and roofed with stone, that was used in early medieval Ireland for storage or as a place of refuge within a settlement. This particular example has largely collapsed into itself, leaving a linear hollow roughly five metres long and four metres wide, oriented roughly north-north-west to south-south-east. Most visitors, if they found it at all, would see little more than a grass-covered dip in a field.

What makes it worth a closer look is the single roof lintel that remains apparently in situ at the south-south-east end, a last survivor of what Neary, writing in 1914, described as a structure once roofed with massive flag-stones. Several other loose slabs lie in the immediate vicinity, probably displaced over decades of agriculture and weathering. The souterrain sits within the north-west quadrant of a ringfort, a type of enclosed farmstead common across early medieval Ireland, typically defined by one or more earthen or stone banks. The association of souterrains with ringforts is well documented; they were almost always built as ancillary features within or just inside the enclosing bank, accessible from the interior of the settlement. Here, the relationship between the two structures is still physically apparent, even if both have been considerably reduced by time.