Open. According to public comments, the swimming pool of Zhoushan Dinghai National Fitness Center is open in winter. Zhoushan, a prefecture-level city under the jurisdiction of Zhejiang Province, is a city in the central area of the Yangtze River Delta and an important city in the Shanghai metropolitan area. It is located in the northeast of Zhejiang Province, bordering the East China Sea in the east, Hangzhou Bay in the west and Shanghai in the north. The terrain is inclined from southwest to northeast, and the southern island is large, with high altitude and dense arrangement; North Island is small, low-lying and sparsely distributed. Surrounded by the sea, it has a subtropical monsoon climate.