In 1943, thousands of Allied Prisoners of War and Asian labourers worked on the Death Railway under the imperial Japanese army in order to construct part of the 415 km long Burma-Thailand railway. The black iron bridge is a part of the Death Railway linking Thailand with Burma. Still in use today, the bridge was the target of frequent Allied bombing raids during World War II and was rebuild after war ended. The Bridge on the River Kwai is a British 1957 World War II film by David Lean ( stars Alec Guinness, Sessue Hayakawa, Jack Hawkins and William Holden) based on the novel The Bridge over the River Kwai by French writer Pierre Boulle.