Go looking for it on the ground, however, and there is nothing to see. No opening in the earth, no stonework, no depression. The feature has vanished entirely from the visible landscape, leaving only its cartographic ghost behind.

What the OS maps record as a cave was identified by a researcher named Henry, writing in 1957, as a souterrain, positioned at the south-western side of an associated hut. A souterrain is an artificially constructed underground passage or chamber, typically built during the early medieval period in Ireland, often used for storage or as a place of refuge. They were generally lined and roofed with stone, and could range from a simple short tunnel to a more elaborate series of linked chambers. The Carhan example was catalogued as part of a broader archaeological survey of the Iveragh Peninsula published in 1996, which drew together evidence for the dense and often fragmentary archaeological record of South Kerry. By the time that survey was compiled, no visible trace remained above ground, and nothing has come to light since to change that assessment.