The Dujiangyan is situated in the western portion of the Chengdu flat lands at the confluence between the Sichuan basin and the Qinghai-Tibet plateau. Dujiangyan is famous for its irrigation system amed Dujinagyan which was originally constructed around 256 BC by the State of Qin as a water conservation and flood control project. The system's infrastructure is located on the Min River, which is the longest tributary of the Yangtze, in Sichuan, China. Originally the Min river rushed down from the Min Mountains, but slowed abruptly after reaching the Chengdu Plains, causing the watercourse to fill up with silt, making the surrounding area extremely prone to flooding. Li Bing, then governor of Shu for the state of Qin, and his son headed the construction of the Dujiangyan, which harnessed the river using a new method of channeling and dividing the water rather than simply following the old way of dam building. It is still in use today to irrigate over 5,300 square kilometers of land in the region. The Dujiangyan along with the Zhengguo Canal in Shaanxi and the Lingqu Canal in Guangxi are collectively known as the "three great hydraulic engineering projects of the Qin dynasty." Dujiangyan has three attractive elements: rivers, mountains, and pandas.