A souterrain, to use the archaeological term, is an artificial tunnel or chamber built during the early medieval period, typically between the seventh and twelfth centuries, and constructed from dry-stone walling with large capstones laid across the top. They are found across Ireland in considerable numbers, often associated with ringforts or early settlement sites, and their purpose has been debated for generations. Cold storage, refuge, ritual use, or some combination of all three are the explanations most commonly proposed.

The souterrain at Bawnaskehy is recorded as a monument in County Kerry, though the details of its construction, dimensions, and immediate landscape context remain sparse in what has so far been made publicly available. Kerry has a notable concentration of such features, shaped in part by the county's dense early medieval settlement patterns and the enduring tradition of building in stone where timber was less plentiful. The placename Bawnaskehy is itself of some interest, with "bawn" deriving from the Irish "bábhún", an enclosure, which may or may not point to a broader complex of early activity in the area, though that connection should not be overstated without firmer evidence.