It is only about three metres from solid ground, but the accumulated mud makes it entirely unreachable on foot. What was once a north-facing slope above the valley of the River Liffey is now submerged, and this stone, which would originally have stood on dry land overlooking that valley, finds itself stranded at the waterline, partly swallowed by the reservoir created when the Liffey was dammed in the 1940s.

The stone itself is likely granite, roughly 1.3 metres tall from subsoil to tip, though only 85 centimetres of that is visible above the mud. It tapers to a point, leaning slightly northward, and its rectangular base measures 35 by 25 centimetres, with the long axis oriented at approximately 290 degrees magnetic, broadly west-northwest. A relict field bank runs off to the northeast of it, now betrayed only by the stumps of bushes at the shoreline, and this boundary is old enough to appear on the Cassini edition of the Ordnance Survey map, which dates from the late nineteenth and early twentieth century. The stone stands just to the northwest of this bank, suggesting it may once have marked a boundary, a threshold, or something less easily categorised. From its position, there are open views from west through north to east, and three passage tombs, the megalithic chambered monuments common to the hilltops of this region, are visible on the mountains to the east, a reminder that this landscape was already considered significant long before any field bank was drawn across it.

The point of land the stone occupies is accessible to the eye from the shore, and the sight of a prehistoric monument jutting into a twentieth-century reservoir is a quietly disorienting one. The steep shoreline and the deep silt mean there is no prospect of a closer inspection, but the firm ground beneath the mud, felt at around 45 centimetres below the surface, is a detail that somehow makes the whole scene more present, the old landscape still there, just out of reach.