ireland is the third-largest island in europe, and the twentieth-largest island in the world. it lies to the north-west of continental europe and is surrounded by hundreds of islands and islets. to the east of ireland, separated by the irish sea, is the island of great britain. politically, the state ireland (described as the republic of ireland) covers five-sixths of the island, with northern ireland, part of the united kingdom, covering the remainder in the north-east.