Holy wells, a feature of the Irish landscape that predates Christianity but was absorbed into it, were typically venerated as sources of healing or spiritual merit, and this one is no exception. The well itself is barely more than a hollow in the improved pasture, with a deeper hole towards its southern end that is thought to be the original source. Eleven metres to the south stands a mature beech tree, known locally as the Coola tree, which serves as a quiet landmark in an otherwise ordinary agricultural field.

The well takes its name from Mac Duach, an early Irish saint also associated with Kilmacduagh in County Galway, a monastery he is said to have founded in the seventh century. The connection to this part of Tipperary runs through the nearby site of Teampull Mhic Duach, a ruined church once located in the townland of Alleen-Ryan. Writing in 1930, O'Flanagan recorded that the well was still being visited by a few pilgrims on Saturdays and by considerable crowds on Good Fridays, a pattern of devotion that tied the site into the wider Catholic penitential calendar. What makes the place quietly affecting is not just its religious history but the evidence of communal care around it. Local memory holds that the people of the area took turns cleaning the well and took genuine pride in maintaining it, a form of collective stewardship that speaks to how seriously such sites were once regarded in everyday rural life.