This book re-assesses archaeological research into holy well sites in Ireland and the evidence for votive deposition at watery sites throughout northwest European prehistory. Ray examines a much-ignored and diminishing archaeological resource; moving beyond debates about the possible Celticity of these sites in order to gain a deeper understanding of patterns among sacred watery sites. The work considers how and why sacred springs are archaeologically-resistant sites and what has actually been found at the few excavated in Ireland. Drawing on the early Irish literature (the myths, hagiographies, penitentials and annals), the author gives an account of pre-Christian supermundane wells in Ireland and what we know about their early Christian use for baptism, and concludes by considering the origins of “rounding” rituals at holy wells.