the Aran Islands a group of three small islands off the west coast of the Republic of Ireland. Islands (pop., 2001: 543), Galway Bay, western Ireland. The group of small islands, totaling about 18 sq mi (47 sq km), includes Inishmore (or Aranmore), Inishmaan, and Inisheer. Their main town is Kilronan on Inishmore. The islands contain impressive prehistoric and early Christian forts. Novelist Liam O'Flaherty was born on Inishmore