They are officially attributed to St Brendan, the sixth-century navigator saint, and the name is there on the old Ordnance Survey maps. But ask the islanders and the dedication shifts entirely: locally, both the well and the monument beside it are associated with St Columcille, and it is on his feast day, not Brendan's, that people come to visit. The cartographic record and living tradition have simply never agreed.

The well itself is not a constructed feature but a natural pothole worn smooth into a flat rock outcrop, roughly thirty centimetres across. A semicircular drystone cairn has been built around its southern side, lending it a degree of formality it would not otherwise possess. About a metre to the south-east stands the monument proper, a D-shaped cairn of similar scale, around a metre and a half high. Coins and the remains of flowers are tucked among the stones of both structures, traces of continuing devotion. A third element lies fifty metres further west, just below the high-water line: another natural pothole, this one a little larger, with an irregular cairn piled above it. This one carries the name St Brendan's Well in local usage, which adds another layer of confusion to the attribution. The geographer and historian Roderic O'Flaherty noted the site in 1684, describing it as a place in memory of St Brendan, so the association is at least that old, even if the saint in question has apparently been a matter of local negotiation ever since.

The site is small, and easy to underestimate. What makes it worth pausing over is less the physical scale of the cairns than the quiet persistence of use they represent: coins pressed into the stones, flowers left and replaced, a pattern of observance that has continued across centuries while the question of whose memory is being honoured has remained, in some sense, open.