The stone at Friarstown in County Limerick has had exactly that experience, and its documentary trail offers a small but telling study in how these ancient markers shift, disappear, and reappear across the centuries.

The stone was recorded in 1840 in the Ordnance Survey Letters for Caherelly Parish, where it appears under the name Cloch a Líagáin, meaning roughly the stone of the pillar or pin, as líagán in Irish refers to a standing stone or pillar. At that point it was described as measuring five feet in height and three feet in diameter, standing upright in a green field near the centre of the Friarstown townland, a few yards west of Ahavackig, the place-name Aith an Bhacaigh. By 1916, however, a researcher named Lynch found it lying prostrate beside an old road known as Boherliagan, which takes its own name from the same Irish root, suggesting the road and the stone had long been understood as companions in the landscape. Then, on the 1928 Ordnance Survey six-inch map, the stone leaves no visible surface trace at all, as though it had simply ceased to exist for cartographic purposes. It now sits roadside, adjacent to a concrete-block wall, its situation rather more ordinary than its history.

The stone is roadside and accessible without any special effort, though its current setting beside a modern wall does little to frame it as something ancient. Because the 1928 map records no surface trace, its re-emergence in the archaeological record is itself worth noting when you arrive. The old road name Boherliagan, the road of the standing stone, is a useful thing to keep in mind, as it suggests the stone once oriented the local geography around itself rather than the other way around. There is no formal signage or managed access; this is the kind of site that rewards people who have already done a little reading before they get there.