That combination, easy to walk past without a second thought, is considered a possible indicator of something beneath: a souterrain, an underground stone-lined passage or chamber built during the early medieval period, typically associated with the ringforts that housed farming families across Ireland between roughly the fifth and twelfth centuries. Souterrains were used for storage, shelter, or refuge, and they survive in large numbers across the country, though many, like this one, exist as little more than a suspicion in the landscape.

The site sits within a ringfort, a class of monument so common in Ireland that estimates of their total number run to around 40,000 or more. Ringforts were enclosed farmsteads, their interiors protected by an earthen bank and ditch, and they were the dominant settlement form of early medieval rural life. The souterrain here was noted in a 1994 archaeological survey of the Ballinrobe district compiled by D. Lavelle, which covered the area around Lough Mask and Lough Carra. The language used is cautious: a slight depression and rough vegetation may indicate a souterrain. No excavation appears to have confirmed what, if anything, lies below.