Bullauns are among the more quietly puzzling objects in the Irish archaeological record. The term refers to a boulder or outcrop bearing one or more cup-shaped depressions, and while some are associated with early Christian sites and holy wells, their origins and precise purposes remain disputed. Were they used for grinding, for ritual, for collecting rainwater thought to carry curative properties? The honest answer is that scholars are not entirely certain, and that ambiguity is part of what makes them worth attention.