Open the door. According to the inquiry of Yancheng local treasure, Yancheng Library normally opens on National Day. Opening hours are: 7 am to 22 pm. Yancheng, also known as Piaocheng, Deng Ying, Baijiang City and Du Yan, is a prefecture-level city under the jurisdiction of Jiangsu Province, a city in the central area of the Yangtze River Delta, and a third-tier city. It is located in the eastern coastal area of China, in the east of Jiangsu Province, bordering the Yellow Sea in the east and Nantong in the south.