Rivers in North Thailand

North Thailand has lots of rivers and two mega-rivers ... Mee Khong River & Chayao Phraya River ... Mae Nam and control of passage on these liquid highways have been the foundations on the Siam, Lanna, Burmese, and Ankor Kingdoms (same priciple as in Roman/Chinese/Eygptian/Sumerian Empires control the commerce).

Mee Khong River ... starts in northwest China and flows down to Cambodia and Vietnam - Chiang Saen

Chao Phraya River ... Thailand and Bangkok's mainlife line. Nakhon Sawan is at the confluence the Ping and the Nan rivers to form the Chao Phraya.

Kok River ... river flowing from Tha Ton > Chiang Rai

Ping River ...river flowing from Lamphun > Chiang Mai (West Fork of Chao Phraya River)

Nan River ... river flowing from Phitsanulok (East Fork of Chao Phraya River)

Yom River ... river flowing from Phrae > Sukothai (tributary of the Nan River)

tributary rivers of North Thailand

Yom River Basin (ยม) ... tributary of the Nan River (which is a tributary of Chao Phraya River) - Phrae
Tributaries of the Yom include Pong, Ngao, Ngim, Sin, Suat, Pi, Mok, Phuak, Ramphan, Lai, Khuan and Kam Mi Rivers.

Greater Nan Basin (comprising the Nan Basin and the Yom Basin, and usually divided as such in drainage analyses)
Greater Ping Basin (comprising the Ping Basin and the Wang Basin, and usually divided as such in drainage analyses)