The structure is modest in its dimensions, roughly two and a quarter metres across, with a northern entrance so narrow, around thirty centimetres wide, that entering it would require deliberate, even effortful movement. That narrowness is unlikely to be accidental. Holy wells in Ireland were frequently used as penitential stations, places where people came not for leisure but for the formal, sometimes physically demanding practice of rounds, prayers, and acts of contrition. The architecture here seems to reinforce that purpose, making access a small ordeal in itself.

Drystone construction, in which stones are laid and fitted without any binding mortar, is one of the oldest building traditions in Ireland, and the chamber here belongs to a type that appears across the country wherever a spring attracted sustained devotion. The site at Bullaun follows a familiar pattern: a natural water source invested over time with religious significance, enclosed by human hands, and woven into local ritual life. Some collapse along the eastern wall has altered the structure since it was in active use, though the essential form remains legible. The well predates any documentary record of it, and its continued existence owes more to the durability of dry-laid stone and the persistence of local memory than to any formal programme of preservation.