Portal tombs, sometimes called dolmens, are among the oldest monument types in Ireland, built during the Neolithic period as burial chambers, typically consisting of two upright portal-stones at the entrance, a backstone, side-stones, and a large capstone overhead. This one has been slowly coming apart for a very long time, and what remains is a kind of freeze-frame of that process.

The chamber faces east and measures 2 metres in length. Of the two large stones that formed the entrance, the southern portal-stone survives at 1.8 metres high, and beside it stands what appears to be a doorstone at 1.4 metres. The northern portal-stone is gone entirely. The side-stones, each originally around 1 metre tall, tell a similar story of slow ruin: the northern one still stands, while the southern has collapsed inward. The backstone, 1.5 metres high, leans inward as well. The roofstone, which would originally have been raised across the whole structure, now rests its front end on the surviving portal-stone while its far end has dropped down into the chamber below. Two additional stones near the inner end of the collapsed southern side-stone are of uncertain origin, and their relationship to the original tomb plan has not been resolved. The structure was catalogued and described by Ruaidhrí de Valera and Seán Ó Nualláin in their 1972 survey of megalithic tombs across the Irish midlands and west.