It is a crannog, an artificial or heavily modified island of the kind built throughout Ireland and Scotland from the Bronze Age well into the early medieval period, constructed as a defended dwelling place in the shallows of a lake. This one, however, is no longer an island in any visible sense. It sits submerged, its presence knowable only to those already looking for it.

What survives is a revetted stone structure, meaning it was built with an outer facing of stone intended to retain and consolidate the mass of the island. Its footprint is triangular rather than the more familiar rounded form associated with many crannogs, measuring roughly ten metres on its north-to-south axis and six and a half metres east to west. Loose patches of rock are scattered across its surface from the north-east to the north-west. The survey that recorded this site in 1994 provides little beyond these dimensions and the fact of its submersion, which itself raises quiet questions. Whether the water level of Lough Carra has risen over centuries, or whether the structure was always partially submerged as a defensive measure, the notes do not say.