It is one of a pair, the two wells lying roughly fifty metres apart in rough grazing land, and together they are known locally as St John's wells. That plural is worth pausing on: two separate sites, side by side on a mountainside, sharing a name and a purpose.

The well itself is roughly rectangular, measuring about 2.1 metres east to west and 1.6 metres north to south, shaped partly by the natural formation of the rock around it. On the south-west face of that same rock, someone has inscribed a small white cross. The dedication to St John gave the site its ritual calendar: rounds were formerly made here on 22 and 23 June, St John's Eve and St John's Day. A pattern day, or "round", at a holy well typically involved circumambulating the site a set number of times, often while reciting prayers, as a form of devotional practice rooted in pre-Christian custom and later absorbed into Catholic observance. At this particular well, the purpose was understood to be the curing of eye ailments, a specialisation that occurs at holy wells across Ireland but always lends a site a very particular character, suggesting centuries of people arriving with something specific to ask for.