A souterrain, from the Old French for "under ground", is an artificial tunnel or chamber built during the early medieval period, typically between the seventh and twelfth centuries. They are found across Ireland in their hundreds, often associated with ringforts, and their exact purpose has long been debated: cold storage for dairy and food, a place of refuge during raids, or some combination of the two. The one at Lackabaun is a quiet presence in the Kerry landscape, recorded but little discussed.

Beyond its classification and location, the specific details of this souterrain remain thinly documented in publicly available sources. What can be said is that Kerry has a notable concentration of these structures, often cut into sloping ground or built from drystone walling and roofed with large lintels. Many were discovered only when farm machinery broke through a roof that had held for a millennium. The townland name Lackabaun, from the Irish leaca bán meaning "white flagstone" or "pale hillside", hints at the kind of open, stony terrain where such monuments tend to survive, overlooked rather than demolished, simply because the ground above them was never worth ploughing too deeply.