Nan River
The Ping River (, , ), along with the Nan River, is one of the two main tributaries of the Chao Phraya River. It originates at Doi Thuai in the Daen Lao Range, in Chiang Dao district, Chiang Mai Province. After passing Chiang Mai, it flows through the provinces of Lamphun, Tak, and Kamphaeng Phet. At the confluence with the Nan River at Nakhon Sawan (also named "Paknam Pho" in Thai), it forms the Chao Phraya River.