Once a famous turus (pilgrimage site), the well continues to attract visitors on 25th November, the feast day of St. Catherine of Alexandria, though in considerably smaller numbers than in its heyday. The dedication to this Egyptian virgin martyr is somewhat unusual for rural Ireland; her cult only became popular in Western Europe after the Crusades, and curiously, she doesn’t appear in either the Martyrology of Donegal or the Feilire of Aengus, two important Irish religious calendars.

Local tradition offers competing explanations for the well’s origins. One tale speaks of a bishop arriving at Killybegs port after a perilous sea voyage, who led his fellow passengers and crew to the Cealla Beaga, “the little churches”, in thanksgiving for their safe deliverance. Upon discovering the well, he blessed it and dedicated it to St. Catherine, placing the entire district under her protection. Another version attributes the shrine’s founding to Spanish Armada sailors who were shipwrecked in Donegal Bay in 1588. The connection between “Cat Castle” and the saint may lie in linguistic corruption, with “Cat” possibly deriving from “Cait”, the Irish form of Catherine.

The well’s history includes a peculiar Victorian incident that has become part of local lore. Around 1850, a Protestant rector named Lodge allegedly had the well filled in with earth, only to have a spring burst forth in his drawing room the following day. His terrified wife convinced him to reopen the well, and the tradition of cleaning it out on St. Catherine’s Eve before the annual pilgrimage has continued ever since. Despite modernisation and changing times, this holy well remains a tangible link to Ireland’s complex religious heritage, where Christian devotion, folk tradition, and maritime history converge in a boggy Donegal field.