Moei River The Moei River forms the border between Thailand and Burma. The river is the scene of clashes between the Tatmadaw and Karen militias. Often Karen people cross the river either in order to enter Thailand as refugees or to go back to Burma. Moei River The Moei River (, , , ) is a tributary of the Salween River. Unlike most rivers in Thailand, the Moei River flows north in a northwest direction. It originates in Phop Phra District, Tak Province, flowing then from south to north across Mae Sot, Mae Ramat, and Tha Song Yang Districts, finally entering the
River systems of Thailand flow into the Mekong. The Mekong is the only river system in Thailand which drains into the South China Sea. The Chao Phraya River system is the main river system of Thailand, as its basin defines much of the region of central Thailand. The Chao Phraya River begins at the confluence of the Ping and Nan Rivers at Nakhon Sawan (also called Pak Nam Pho) in Nakhon Sawan Province. It then flows from north to south for from the central plains through Bangkok to the Gulf of Thailand. In Chai Nat, the river splits into the main river course and