A dispute in Ireland forced St Cybi — a Cornish saint — and his acolytes to relocate in Gwynedd, where the well began to be identified with him.
Gorfodwyd Sant Cybi – sant o Gernyw – a’i acolitiaid i ffoi o Iwerddon oherwydd anghydfod ac adleoli i Wynedd, lle dechreuwyd cysylltu’r ffynnon ag ef.