River systems of Thailand divides into two major branches, the " Tiền Giang" (Front River) and "Hậu Giang" (Back River). These in turn enter the South China Sea through nine estuaries. The following are the principal tributaries of Mekong River which flow through Thailand (tributaries entirely outside the Thai border not shown). The Mekong drains a considerable portion of northeast Thailand. In terms of Thai territory drained, it is second only to the Chao Phraya system. The Salawin River rises in Tibet (Tibetan: རྒྱལ་མོ་རྔུལ་ཆུ།) after which it flows through Yunnan, where it is known as the "Nujiang" River (), although either name can be
Lao River (Thailand) Lao River (Thailand) The Lao River or Mae Lao River (, , ) is a river in Chiang Rai Province, Northern Thailand. It is a tributary of the Kok River, with its mouth near Sum Pratu in Mueang Chiang Rai District. This river gives its name to the Mae Lao District. The Lao River originates in the Phi Pan Nam Range and flows initially northwards across Wiang Pa Pao District and then northeastwards through the districts of Mae Suai, Mae Lao and Mueang Chiang Rai passing just south of Chiang Rai city. The Suai River, which gives its name to