The Bridge on the River Kwai is a 1957 British-American epic war film directed by David Lean and starring William Holden, Jack Hawkins, and Alec Guinness, and featuring Sessue Hayakawa. Based on the novel Le Pont de la Riviere Kwai (1952) by Pierre Boulle, the film is a work of fiction, but borrows the construction of the Burma Railway in 1942 -- 1943 for its historical setting. The movie was filmed in Ceylon (now Sri Lanka). The bridge in the film was near Kitulgala.

Answer this question: bridge on the river kwai fact or fiction? Let's give stream of consciousness first:
The important part for answering this question is: Based on the novel Le Pont de la Riviere Kwai (1952) by Pierre Boulle, the film is a work of fiction, but borrows the construction of the Burma Railway in 1942 -- 1943 for its historical setting.
So, the final answer is fiction.