Seawise Giant, later Happy Giant, Jahre Viking, Knock Nevis, Oppama, and Mont, was a ULCC supertanker that was the longest ship ever, built by Sumitomo Heavy Industries in Yokosuka, Kanagawa, Japan. She possessed the greatest deadweight tonnage ever recorded. Fully loaded, her displacement was 657,019 tonnes (646,642 long tons; 724,239 short tons), the heaviest ship of any kind, and with a laden draft of 24.6m (81ft), she was incapable of navigating the English Channel, the Suez Canal or the Panama Canal. Overall, she is generally considered the largest ship ever built.[5][6] She was sunk during the Iran–Iraq War, but was later salvaged and restored to service.[7] She was last used as a floating storage and offloading unit (FSO) moored off the coast of Qatar in the Persian Gulf at the Al Shaheen Oil Field.[8]