The Ruak originates within the hills of the
Daen Lao Range,
Shan State (
Burma), and becomes the boundary river between Thailand and Burma at the confluence with the
Mae Sai River near the northernmost point of Thailand. It then meanders eastwards until it empties into the
Mekong River at
Ban Sop Ruak, Tambon Wiang,
Chiang Saen District,
Chiang Rai Province. The boundary section of the river is long. ==See also==