What is known about it amounts to a handful of measurements and a single map reference, and yet those details sketch something genuinely intriguing: a souterrain, a type of dry-stone underground structure commonly built in early medieval Ireland, often used for storage or refuge, that extends across several chambers for a total length of nine metres.

The structure was marked on the Ordnance Survey six-inch map of 1938, which remains the clearest evidence of its position. A separate reference by McCarthy in 1977 recorded a souterrain in an orchard in the same general area, and it is possible, though not confirmed, that both accounts describe the same site. The first chamber, the only one examined in any detail, was stone-built, measuring 1.21 metres wide and 1.8 metres high, dimensions consistent with a person moving through it in a low crouch. Beyond that chamber the structure was not fully explored, meaning whatever lies further along its nine-metre run remains undocumented. The discrepancy between the orchard location noted by McCarthy and the tree plantation recorded elsewhere adds a further layer of uncertainty, and it is unclear whether the trees themselves grew up around a feature that was already falling out of use, or whether the location was simply misremembered or imprecisely mapped at one point or another.