It is the kind of thing that most people walk past without a second glance, which makes its claim all the more quietly extraordinary: local tradition holds that this is the very well at which the Irish chiefs refreshed themselves during the Battle of Clontarf.

The Battle of Clontarf was fought on Good Friday, 1014, and stands among the most consequential engagements in medieval Irish history, the moment at which the High King Brian Boru, whose name appears in the Anglicised form "Boroimhe" on the inscription, led his forces against a Viking and Leinster alliance. Brian himself died during or after the battle, which has given the site and its surrounding landscape a long afterlife in local memory. The association of this particular well with the Irish chiefs was recorded by O'Gorman in 1879 and by Ryan in 1938, suggesting the tradition had already been circulating for some considerable time before either writer set it down. Wells of this kind often accumulated legend precisely because they were practical, durable features of a landscape, the kind of place an army would genuinely have needed.

The well is located along Castle Avenue in Clontarf, and the inscribed doorway with its water dispenser is visible from the street. There is no grand approach and no site to manage; it is simply there, worked into the fabric of a residential avenue. The dispenser suggests the well, or at least its memory, was at some point adapted for public use, which gives the whole thing an oddly functional quality. If you are in the area and looking for it, the decorative surround and inscription are the markers to watch for; the well itself is easy to miss if you are not already expecting it.