Endurance was a British Antarctic exploration ship famously used by Sir Ernest Shackleton during the Imperial Trans-Antarctic Expedition (1914–1917). Built in 1912 and specially designed for polar conditions, Endurance had a reinforced wooden hull meant to withstand heavy ice pressure. In January 1915, the ship became trapped in pack ice in the Weddell Sea. Despite months of drifting, the crushing force of the ice eventually proved overwhelming. On November 21, 1915, Endurance was slowly crushed