No plaque marks it, no heritage trail points towards it. The most that can be said with confidence is that it once existed, and that it is gone in the practical sense, even if not entirely erased.

The well was dedicated to St. Ossan, also recorded as Assan, and its existence was documented by P.W. Joyce in 1912, who noted that it had formerly occupied a field situated between the local church and the railway station at Clontarf. Holy wells, which are freshwater springs or pools associated with early Christian saints and venerated for centuries through patterns, pilgrimage, and folk custom, were once a familiar feature of the Irish landscape, often marked by votive offerings and seasonal gatherings. By the time Joyce recorded this one, it had already been covered over, its water redirected underground to join the Santry River. What remained on the surface were two quiet indicators: a shallow depression in the ground and a bush, the kind of incidental markers that can easily be mistaken for nothing at all. By 1958, when the folklorist Caoimhín Ó Danachair surveyed such sites, even those modest traces were insufficient to pin down a precise location.

There is, practically speaking, nothing to visit here in the conventional sense. The well has no confirmed coordinates and no visible remains. What the site offers instead is a different kind of interest, the experience of looking at an unremarkable stretch of north Dublin suburb and knowing that something was once there, named for a saint, used by local people, and then quietly buried under the expanding city. Anyone curious enough to stand in the general area between St. John the Baptist Church and Clontarf railway station might find it a useful exercise in how thoroughly urban development can absorb a landscape's older layers.