Introduction to Butterfly Island: Butterfly Island is a small island built to commemorate Shanghai movie star Hu Die filming "Salt Tide" in Nanbei Lake in 1931. It looks like a butterfly. There is a Shanhai Pavilion built in the island, with a total of three floors. Each layer is open and cave-like, with mountains on three sides and one facing the sea. Although the pavilion is small, it can accommodate the scenery of lakes, mountains and sea.