From its source in the treeless Alps of Kunlun, the Yangtze River winds 3.900 miles through the country from west to east. It is the longest river in China and the third longest in the world. It is also an origin of the ancient Chinese civilization. The Yangtze passes through the spectacular Yangtze Gorges. With its numerous tributaries and feeders, the Yangtze provides a great transportation network through the heart of some of the most densely populated and economically important areas in China.