It is not especially tall, rising only about 0.85 metres above the ground, and its broad triangular shape gives it a squat, almost hunched appearance. What makes it quietly curious is precisely this modesty: a prehistoric standing stone, a monolith erected by human effort for purposes we can no longer be certain of, blending so thoroughly into the boggy hillside that it could easily be passed off as a natural feature of the landscape.

Standing stones are among the most common yet least understood prehistoric monuments in Ireland. They were erected during the Bronze Age, roughly between 2500 and 500 BC, and are thought to have served a range of functions, from territorial markers to sites of ritual significance, though no single explanation fits every example. This particular stone measures 0.97 metres in length and 0.3 metres in thickness, with its long axis running north to south. Normally, archaeologists look for packing stones around the base of a standing stone, smaller rocks deliberately placed to stabilise the monolith in the ground. Here, no such packing stones are visible, a fact noted by local observer Ivor Kenny in September 2014. The reason is straightforward: around 0.2 metres of peat has accumulated over the ground surface since the stone was first raised, concealing whatever arrangement may lie beneath. The peat itself is a reminder of how much the landscape has changed since the monument was built, the open ground of the early Bronze Age gradually overtaken by the wet, acid conditions that produce bogland.

The stone sits on the south-western slope of Two Rock Mountain, on the northern side of the Glencullen River valley, in the Dublin Mountains just south of the city. Access to this part of the mountain is on foot across open moorland, and the terrain is typical of the area: uneven, wet underfoot for much of the year, and without clear signposting to minor archaeological features. Visitors planning a trip would do well to go in dry summer conditions when the ground is at its firmest, and to carry a decent map or GPS reference, as the stone is low enough to be easy to miss. Once you are close, the triangular profile becomes more legible, and it is worth pausing simply to consider that someone, several thousand years ago, chose this particular spot on this particular hillside and decided it was worth the effort.