Thule Island, also called Morrell Island, is one of the southernmost of the South Sandwich Islands, part of the grouping known as Southern Thule. It is named, on account of its remote location, after the mythical land of Thule, said by ancient geographers to lie at the extreme end of the Earth. The alternative name Morrell Island is after Benjamin Morrell, an American explorer and whaling captain. The island was espied by James Cook and his Resolution crew on 31 January 1775 during his attempt to find Terra Australis.