The Knock Nevis is a floating storage and offloading unit (FSO) currently owned by the Norwegian company Fred Olsen Production. The unit was previously a supertanker and as such held the record for the world's largest ship. As a tanker the ship was known under the names Seawise Giant, Happy Giant, and Jahre Viking.

General Characteristic
Tonnage: 260,941 GT (214,793 NT)
Length: 458.45 m (1,504.10ft)
Beam: 68.8 m (225.72ft)
Draft: 29.8 m (97.77ft)
Capacity: 564,650 DWT

Knock Nevis was built in 1979 at Sumitomo Heavy Industries's Oppama shipyard as Seawise Giant. The ship was built for a Greek owner who was unable to take delivery of the ship.

In terms of length, Knock Nevis has a length overall of 458.45m (1,504ft), making her the largest ship ever constructed. The vessel is longer than many of the world's tallest buildings are tall, for example the Petronas Twin Towers at 452metres (1,480ft). She is smaller than the Sears Tower at 527.3 metres (1,730ft), and Taipei 101 at 509.2metres (1,671ft), and considerably smaller than the skyscraper Burj Dubai, currently under construction, at 636metres (2,090ft).