Amazing China: Qilian Mountains

The Qilian Mountains, across China's Gansu and Qinghai provinces, stretch for about 800 kilometers from east to west. It's a huge mountain range composed of many parallel mountains. About one third of the peaks of the Qilian Mountains are more than 4,000 meters above the sea. There are more than 3,000 glaciers storing tens of billions of cubic meters of water in solid form. If all the glaciers were to melt, the water generated would be enough for a city of 20 million people to use for about 20 years.