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
Burma Railway jungle with its heat and humidity. All of that makes this railway an extraordinary accomplishment." The total freight carried during the war was 500,000 tonnes by two Japanese Army divisions. The line was closed in 1947, but the section between Nong Pla Duk and Nam Tok was reopened ten years later in 1957. On 16 January 1946, the British ordered Japanese POWs to remove the 4 km rail between Nikki and Sonkrai. The railway link between Thailand and Burma was to be separated again for protecting British interests in Singapore. After that, the Burma section of the Railway was sequentially