The River Kwai, more correctly Khwae Noi, is a river in western Thailand.
It rises to the east of the Salween in the north–south spine of the Bilauktaung range near, but not over the border with Burma. It begins at the confluence of Ranti, Songkalia and Bikhli Rivers.
At Kanchanaburi it merges with the Khwae Yai River to form the Mae Klong River, which empties into the Gulf of Thailand at Samut Songkhram.
