stylistic:tone, quality:corruption, quality:correction, stylistic:style_transfer
Geography

At 1,600 metres (5,200 ft) above sea level, Lanzhou lies in China's northwest geographical center. The metropolitan area covers more than 20 square kilometres (7.7 sq mi) of urbanisation along the southern banks of the Yellow River, which flows through from west to east. The Qilian Ranges, Mt. Pingliang, and Mt. Kongtong are located on the south and north sides of the city.

Lanzhou is situated on the upper reaches of the Yellow River where it emerges from the mountains and has been a center since early times, being at the southern end of the route leading via the Hexi Corridor across Central Asia. It commands the approaches to the ancient capital area of Chang'an (modern Xi'an) in Shaanxi province from both the west and the northwest, as well as the area of Qinghai Lake via the upper waters of the Yellow River and its tributaries.