Introduction to Swan Lake: On the east coast of Rongcheng, which is 45 kilometers long from north to south, there are continuous lagoons scattered around. These lakes are bright and attractive, like pearls. The lagoon is surrounded by land on three sides and connected to the sea on one side, forming a vast water surface of 600 hectares. In the intertidal flats on the seaside side, a large amount of seaweed grows, forming a huge seagrass field; between the rise and fall of the tide, the seawater and the lagoon convection, adding rich food to the lake. Every year in early November, many whooper swans fly from Siberia, Inner Mongolia and Heilongjiang and stay here. The white angels stay here until February and March before they start to disperse and return one after another.