No hollow in the earth marks its presence, no depression in the grass suggests what lies beneath. The site is recorded on local knowledge alone, which gives it an almost folkloric quality; a thing known but not seen, passed down rather than excavated.

The passage is a souterrain, a type of underground structure built during the early medieval period, typically associated with ringforts. Ringforts were enclosed farmsteads, usually circular, defined by one or more earthen banks and ditches, and they served as the basic unit of rural settlement in Ireland for much of the first millennium. Souterrains were dug within or beside them, their walls and roofs constructed from dry-laid stone, and they are thought to have been used for cold storage, refuge, or both. In Dawstown, the ringfort that once contained this souterrain has been levelled, most likely through agricultural clearance over the centuries, leaving nothing visible on the surface. The underground passage, better protected from the plough, may well have survived intact beneath the soil while every trace of the enclosure above it was erased.