The Changjiang River, or the Yangtze River, has a total length of more than 6,300 km. It is the longest river in China and the third longest one in the world. It rises in the Qinghai-Tibet Plateau and flows through many provinces and cities. The middle and lower reaches of the river have been called the cradle of Chinese civilization for their abundance of food produced. Along the two sides of the river is beautiful scenery with many scenic spots and historical sites. For thousands of years, the river has been playing an important role in agriculture，industry, transportation, and war. But in recent years, the river has suffered from industrial pollution and loss of lakes, which has brought seasonal floods.