Fewer pause to notice what lies just to the south-east of it: a low, flattened mound, roughly eighteen metres across, its top occupied by a concrete trigonometric station. That unremarkable lump is what remains of a passage tomb several thousand years old, and the surveying pillar planted on its crown is a neat, if unintentional, illustration of how completely the monument has been absorbed into later uses of the landscape.

Passage tombs are megalithic burial structures in which a stone-lined corridor leads into a central chamber, typically covered by a large circular mound or cairn. This example, and a companion tomb nearby, belong to a wider scatter of such monuments arranged largely along the northern and western slopes of the Dublin and Wicklow mountains, a pattern that suggests deliberate, communal choices about where the dead were placed in the landscape. What survives here is described in the archaeological record as a denuded cairn, meaning the original mound has been robbed of its stone over centuries, leaving only a degraded outline. References to the site appear in published work by Healy as far back as 1875, with later treatments by Price in 1942 and Herity in 1974, suggesting it has been known to antiquarians for well over a hundred years without ever quite escaping obscurity.

The hill is accessible via a well-worn path from the Hellfire Club car park off the R115, the old Military Road above Killakee. The walk to the summit is short but steep in places. Once at the top, the panoramic views open out to the north and east across Dublin Bay and the city; forestry limits what can be seen to the south and west. The tomb sits just downslope from the Hell Fire Club ruin, and it is easy to walk past it without realising what it is. Look for the trigonometric pillar set into the low circular rise in the ground, and bear in mind that the undistinguished earthwork beneath your feet predates the ruined lodge beside it by several millennia.