The three rivers parallel flow refers to the Jinsha River, Lancang River and Nu River, three rivers originating from the Qinghai-Tibet Plateau, traveling parallelly from north to south in Yunnan Province for more than 170 kilometers, crossing between the mountains of Dandan Lika Mountain, Gaoligong Mountain, Nu Mountain and Yunling Mountain. The upper part of the Sanjiang River is in southeast Tibet and the lower part is in Yunnan Province. The Sanjiang River is the most abundant geological and geomorphological museum in the world. 40 million years ago, the Indian plate and the Eurasian plate collided, triggering the sharp compression, uplift, cutting of the cross-sectional mountains, the alpine and the river alternately spread, forming the world's unique three rivers parallel running 170 kilometers of natural wonder.