That alone places it in a curious category: a piece of early medieval underground architecture known primarily through local reputation rather than excavation or inspection.

Souterrains are stone-lined passages or chambers built beneath the ground, typically associated with early Christian-period settlements in Ireland. They served various purposes, most likely storage and refuge, and are found across the country in considerable numbers. The one at Keeas is recorded only as locally reputed to exist and to be inaccessible, which leaves open the question of whether it has collapsed inward, become overgrown, or simply been forgotten into the landscape over centuries. Its inaccessibility is not a modern inconvenience but seems to have been part of its known character for some time.