It appears on a map dated to 1720, drawn up long before systematic surveys of the Irish countryside, and it has resisted easy identification ever since. Its outline was recorded, its rough location noted, but what it actually was remains an open question.

The sole documentary evidence for this structure is a map held in the National Library of Ireland (NLI Ms. 2707), produced in 1720. It places the building near Murneen Castle, a fortified structure whose own history belongs to the layered and often turbulent story of landed power in Mayo. Whether the mystery building was a domestic outbuilding, a small estate structure, a religious site, or something else entirely is not known. Its footprint has not been confidently matched to anything surviving on the ground, and no physical remains have been firmly associated with it.