Corcomroe Abbey was founded by the Cistercians in the late twelfth or early thirteenth century and was known as Sancta Maria de Petra Fertili—St Mary of the Fertile Rock. It sits in a limestone valley of the Burren and is noted for its ornate church and the effigy tomb of Conor na Siudane Ó Briain (King of Thomond), a thirteenth-century O’Brien ruler.

Local tradition ties the ruins to a tragic elopement. The story says the poet Cearbhall Ó Dálaigh and Eibhlin (Eileen) Kavanagh fled to the abbey, hoping to be married in secret at midnight on Christmas Eve. Eibhlin’s father discovered their plan, confronted the couple inside the church, and both lovers were killed. Their ghosts are said to return at midnight each Christmas Eve.

Details vary by teller. Some versions date the episode to the fifteenth century; others place it later and link it with the love song “Eileen A Rún.” The Ó Dálaigh poets had connections in this part of Thomond, and one Cearbhall of that family died at Corcomroe in the early 1400s, which may have helped anchor the tale here. There is no contemporary record of a double killing at the abbey; the story is preserved as local folklore that continues to be told about the site.