It is not especially tall, rising to 1.75 metres, and its proportions are almost architectural in their precision: square in plan, measuring 0.65 metres by 0.65 metres, and tapering to a point at the top. That combination of deliberate geometry and complete silence about its origins is what makes it worth attention.

An orthostat, to use the technical term, is simply a large stone set upright in the ground, and this one is made of local granite. It appears on the Ordnance Survey six-inch map of 1843, which confirms it was a recognised feature of the landscape well before modern record-keeping. Its position is not arbitrary. Roughly six metres to the southwest lies a barrow, a mounded prehistoric burial monument, catalogued separately in the archaeological record. Whether the stone and the barrow were raised at the same time, by the same community, or for related purposes, is not something the current evidence settles. The pairing is noted by researchers including Healy and Turner, whose work in the 1970s and 1980s brought the site into the documented record, and the site has since been compiled and reviewed by archaeologists Geraldine Stout and Padraig Clancy.

Glencullen sits in the Dublin Mountains, and reaching the hill crest above the village requires some uphill walking. The old chapel in the village below serves as a useful landmark for orienting yourself before heading up. Visibility from the summit is wide, and the stone's elevated position means it would have been conspicuous from some distance in any direction, which may or may not have been the point. The barrow nearby is easy to miss if you are not looking for it specifically, so it is worth consulting the archaeological record before visiting to know what to expect underfoot.