In a three year journey between 1903 and 1906, Amundsen explored the passage with a crew of no more than six, in the converted 47-ton herring boat Gjøa. Spending winters with ship trapped in ice, he learned from the local Netsilik people about Arctic survival skills that would later prove useful. For example, he learned to use sled dogs and to wear animal skins in lieu of heavy, woolen parkas. Amundsen later led the expeditions to discover the South Pole (1911) and the North Pole (1926).