Endurance was the three-masted barquentine in which Sir Ernest Shackleton and a crew of 27 men sailed for the Antarctic on the 1914–1917 Imperial Trans-Antarctic Expedition. The ship, originally named Polaris, was built at Framnæs shipyard and launched in 1912 from Sandefjord in Norway. When one of her commissioners, the Belgian Adrien de Gerlache, went bankrupt, the remaining one sold the ship for less than the shipyard had charged – but as Lars Christensen was the owner of Polaris, as well as of the yard, there was no hardship involved. The ship was bought by Shackleton in January 1914 for the expedition, which would be her first voyage. A year later, she became trapped in pack ice and finally sank in the Weddell Sea off Antarctica on 21 November 1915. All of the crew survived her sinking and were eventually rescued in 1916 after using the ship's boats to travel to Elephant Island and Shackleton, the ship's captain Frank Worsley, and four others made a voyage to seek help.