Local tradition holds that a souterrain lies within or near it, but the structure has not been visible within living memory, placing it in that curious category of sites known more through inherited knowledge than direct observation.

A souterrain is an underground stone-lined passage or chamber, typically associated with early medieval settlement in Ireland, and often used for storage or refuge. The one at Ardbeg on the Dingle Peninsula belongs, at least in local memory, to this tradition. The site was documented by J. Cuppage in the 1986 Corca Dhuibhne archaeological survey of the Dingle Peninsula, which remains one of the more thorough regional surveys of its kind. By that point, the souterrain was already a matter of oral tradition rather than something surveyors could physically examine or map with confidence. Whether it has been swallowed by vegetation, collapsed beneath the soil, or simply never relocated after earlier disturbance, the record does not say.