The doorstone has collapsed inward, leaving a slightly ruined but remarkably intact outline of a portal tomb, the kind of Neolithic monument, typically dating from around 4000 to 3500 BC, in which a large capstone is propped at an angle over a small rectangular chamber defined by tall paired entrance stones. That a structure of this scale and age sits quietly beside a walking path, shaded by trees and adjacent to fairways, gives it a quality somewhere between the incongruous and the completely natural.

The tomb sits at the foot of Muck Rock, tucked along a pathway under tree cover at the edge of Deer Park golf course. The chamber itself is modest, measuring 2.6 metres in length and just over a metre wide, with an entrance oriented to the south-east. The two portal stones stand at 2.75 metres and 2.45 metres respectively, and the great roofstone above them measures 5.2 metres long, 4.2 metres wide, and nearly 2 metres deep, a substantial slab by any reckoning. The monument was documented by Borlase in 1897 and later by Ó Nualláin in 1983, and the site record was compiled by Geraldine Stout and updated by Christine Baker.

The tomb is accessible on foot via the pathway that runs along the northern edge of the golf course at Howth Demesne. Tree cover means the light is filtered and the stone can be easy to pass without noticing, so it is worth slowing down once you are near the base of Muck Rock and looking into the woodland edge. The collapsed doorstone gives the chamber an unsettled appearance from inside the entrance, but the roofstone above remains firmly in place, resting on the upper edges of the portals as it has for millennia. The site is unenclosed and accessible year-round, though the path can be muddy in wetter months.