A poem addressed to Tomaltach an Einigh mac Diarmata (King of Moylurg 1421-58) tells the story of the Hag of Lough Key who used (or abused) Cormac MacDermott's (king 1218-44) hospitality by staying on the Rock for a full year, and laid upon the McDermotts the obligation of perpetual hospitality.
In 2014 the island and castle featured in an episode of sitcom Moone Boy, as the residence of the mysterious "Island Joe." .