Sir Earnest Shackleton was the leader of three Antarctic expeditions at the turn of the 20th century. On his second expedition his ship, Endurance, became trapped in the frozen Weddell Sea and was crushed, leaving his crew of 28 stranded on the ice. After months of living in makeshift camps on the ice floe the crew took to the lifeboats and made their way to inhospitable Elephant Island, where they set up a camp with overturned boats as their only shelter. Shackleton and five others then completed an 800-mile voyage to South Georgia in the remaining lifeboat, after which they had to cross a forbidding mountain range to reach a whaling station where help could be obtained. In the end, all were rescued with no loss of life.