Sai River (Thailand)

Sai River
View of the river swollen by the rainy season
Location
CountryMyanmar and Thailand
Physical characteristics
Source 
  locationDaen Lao Range, Shan Hills
Mouth 
  location
Ruak River SE of Tachileik Airport
  coordinates
20°27′52″N 99°57′17″E / 20.46444°N 99.95472°E / 20.46444; 99.95472
  elevation
380 m (1,250 ft)

Sai River (Thai: แม่สาย or แม่น้ำสาย; RTGS: Mae Sai or Maenam Sai; Thai pronunciation: [mɛ̂ː.sǎːj / mɛ̂ː.náːm.sǎːj]), formerly known as the River of Lawa (Thai: แม่ละว้า; RTGS: Mae Lawa), is a river that forms the natural border between Thailand and Myanmar at Tachileik and Mae Sai Districts. Mae Sai town, where the bridge crossing the international border is located, is named after this river. It is a tributary of the Ruak River, itself a tributary of the Mekong.