The Jeannette Expedition of 1879–1881, officially the U.S. Arctic Expedition, was an attempt led by George W. De Long to reach the North Pole by pioneering a route from the Pacific Ocean through the Bering Strait. The premise was that a temperate current, the Kuro Siwo, flowed northwards into the strait, providing a gateway to the Open Polar Sea and thus to the pole. This theory proved illusory; the expedition's ship, USS Jeannette and its crew of 33, was trapped by ice and drifted for nearly two years before she was crushed and sunk, north of the Siberian coast. De Long then led his 32 men on a perilous journey by sled, dragging the Jeannette's whaleboat and two cutters, eventually switching to these small boats to sail for the Lena Delta in Siberia. During this journey, and in the subsequent weeks of wandering in Siberia before rescue, 20 of the ship's complement died, including De Long.