Taihu Lake is the third largest freshwater lake in China and one of the five largest freshwater lakes in the middle and lower reaches of the Yangtze River. The shape of the lake is like a crescent moon protruding westward. In the form of lake shore, the south shore is a typical circular coastline, and the northeast coast is tortuous with many bays, and the headlands and lakes are alternately distributed. The lake area calculated by the lakeshore is 2427.8 square kilometers. Taihu Lake has 5/kloc-0 islands with a total area of 89.7 square kilometers. Therefore, the actual water surface area of Taihu Lake is 2338. 1 1 square kilometer, and the coastline bus is 405 kilometers. Average water depth1.89m. It can be seen from the topography of the lake bottom that the topography of the lake basin is inclined from east to west, and the shape of the lake basin is shallow dish.

Taihu Lake was called "Zhenze" and "Giant Canal" in ancient times, also known as "Five Lakes" and "Lize". It is a relic of an ancient coastal lake, located at the junction of Jiangsu and Zhejiang provinces, in the south of the Yangtze River Delta. About 6.5438 million years ago, Taihu Lake was still a big bay, but it was gradually isolated from the sea in the process of seawater desalination and became an inland lake.