Gansu, located in the northwest of China, the Yellow River crosses Lanzhou, dividing the land into the east and the west of the river, a narrow corridor of about 1,000 kilometers squeezed by the mountains to the south and north, and a slice of oasis, linking the Central Plains and the outside of the country. Our flight starts from central Gansu, encountering a different kind of Loess Plateau. Through the tunnel of time and space, overlooking the past and present of farming civilization, downstream to see how a large river changes color, and finally meet an ancient city by chance.
