Shanghai's ancestors used to live along the river. Zhu jiaxi, a water conservancy expert, said: "Suzhou river was much wider than it is now and Huangpu river is one of its tributaries." After Shanghai opened its port in 1843, it embarked on the road of developing the business by opening the port and developing the market by vitalizing the business. From the beginning of the 20th century, Shanghai began to fill up the river and build roads on a large scale.