The bridge over the Mae Klong (or Kwai Yai, or whatever) really was part of the death railway, built with prisoner and slave labor by the Japanese during World War II. There were actually two bridges built over the river here. A wooden bridge like you see built in the movie (which was actually shot in Sri Lanka) was built first about 100 meters up-river from the current bridge to expedite construction on the line beyond the river. The concrete and steel "main" bridge was added during the war when the steel became available.
Both bridges were bombed by allied planes near the end of the war. The squarish center spans of the bridge are post-war replacements. The wooden bridge was demolished after the war since its thick structure blocked the flow of the river.
The JEATH War Museum is a war museum in Thailand about the Death Railway built from 1942 to 1943 by Allied POWs under the direction of the Japanese, a part of the Thai-Burma railways.
The museum was founded in 1977 by the chief abbot of Wat Chaichumpol Venerable Phra Theppanyasuthee. It is located on the grounds of a temple at the junction of the Kwai Yai and Kwai Noi rivers in Kanchanaburi and it is a part of the famous River Kwai Bridge.
The acronym JEATH stands for the primary nationalities involved in the construction of the railway: Japanese, English, Australian, American, Thai and Holland.
The museum is divided into two sections, one depicting the construction of the Death Railway which is meant to recreate the quarters used by Allied POWs, and the other consisting of reconstructed bamboo huts containing such items as paintings, drawings and photos of and by former prisoners, weapons, tools, and maps.
Tourist photos are not permitted in Section I of the museum.