Subsequently, Cowper attempted to complete the Northern Sea Route (North East Passage) over the top of Russia. He had an aluminium boat, 14.6m "Polar Bound", built and took it round Cape Horn and up the west coast of the Americas in 2002, but was refused permission by the Russian authorities. He turned east and completed the Northwest Passage again, in two summers, from west to east, becoming the first person to have completed an east to west and west to east single-handed transit. He then prepared "Polar Bound" for another attempt, should permission be given by Russia.