The major railway bridge described in the novel and film did not actually cross the river known at the time as the Kwai. However, in 1943 a railway bridge was built by Allied POWs over the Mae Klong river—renamed Khwae Yai in the 1960s as a result of the film—at Tha Ma Kham, five kilometres from Kanchanaburi, Thailand."The Colonel of Tamarkan: Philip Toosey and the Bridge on the River Kwai" , published by the National Army Museum on 03-04-2012. Retrieved 09-24-2015. Boulle had never been to the bridge. He knew that the railway ran parallel to the Kwae for many miles, and he therefore assumed that it was the Kwae which it crossed just north of Kanchanaburi. This was an incorrect assumption. The destruction of the bridge as depicted in the film is also entirely fictional. In fact, two bridges were built: a temporary wooden bridge and a permanent steel/concrete bridge a few months later. Both bridges were used for two years, until they were destroyed by Allied bombing. The steel bridge was repaired and is still in use today.
The major railway bridge described in the novel and film did not actually cross the river known at the time as the Kwai However, in 1943 a railway bridge was built by Allied POWs over the Mae Klong river—renamed Khwae Yai in the 1960s as a result of the film—at Tha Ma Kham, five kilometres from Kanchanaburi Thailand."The Colonel of Tamarkan: Philip Toosey and the Bridge on the River Kwai" , published by the National Army Museum on 03-04-2012. Retrieved 09-24-2015. Boulle had never been to the bridge. He knew that the railway ran parallel to the Kwae for many miles, and he therefore assumed that it was the Kwae which it crossed just north of Kanchanaburi. This was an incorrect assumption. The destruction of the bridge as depicted in the film is also entirely fictional. In fact, two bridges were built: a temporary wooden bridge and a permanent steel/concrete bridge a few months later. Both bridges were used for two years, until they were destroyed by Allied bombing. The steel bridge was repaired and is still in use today