saint of Rhoscolyn (Anglesey), titular of the parish church there. About half a mile away are substantial remains of his well, contained inside a small square stone building. This probably represents, like the examples of Seiriol and Cybi, the primitive settlement of a hermit who later founded the local church, perhaps in the 7th century. A later dedication to an early saint is another possible explanation.
An Inventory of the Ancient Monuments in Anglesey (1937), p. 146.