Amundsen Gulf is a gulf located mainly in the Inuvik Region, Northwest Territories, Canada with a small section in the Kitikmeot Region of Nunavut. It lies between Banks Island and Victoria Island and the mainland. It is approximately 250 mi (400 km) in length and about 93 mi (150 km) across where it meets the Beaufort Sea. The Amundsen Gulf was explored by Norwegian explorer Roald Amundsen between 1903 and 1906. The gulf is at the western end of the famous Northwest Passage, a route from the Atlantic Ocean to the Pacific.