Aine
Aine (aw-ne). The fairy goddess to whom, with her sister Fenne (or Finnen), Knock Aine and Knock Fennine on the shores of Lough Gur are dedicated. They were the daughters of Egogabal, a king of the Tuatha de Danann.
Of Aine there is a version of the swan maiden story, very similar to those of the Gwragedd Annwn of Wales.
One day, as Aine was sitting on the shore of Lough Gur combing her hair, Gerold, the Earl of Desmond, saw her and fell in love with her. He gained control over her by seizing her cloak, and made her his bride. Their child was Earl Fitzgerald, and the taboo imposed upon his father was that he must never express any surprise at anything his son might do. One night, however, showing off his skill to some maidens, he jumped into a bottle and out again, and his father could not restrain a cry of surprise. Fitzgerald at once left the castle and was seen swimming across the lough in the form of a wild goose towards Garrod Island, under which his enchanted castle was said to lie. At the same time, Aine disappeared into Knock Aine.
This story was collected from informants by Evans Wentz and included in The Fairy Faith in Celtic Countries (p. 79). A somewhat similar story is the more widely known legend of Mullaghmast.
SOURCE:
An Encyclopedia of Fairies: Hobgoblins, Brownies, Bogies, and Other Supernatural Creatures written by Katharine Mary Briggs – Copyright © 1976 by Katharine Briggs