Introduction to the ancient city wall: The ancient city wall of Danzhou was a major project undertaken by Su Chaoyang, the governor of Huaiyuan County in the Ming Dynasty, which lasted one year and cost ten thousand taels of silver. The city wall is 879 meters long, 5.3 meters high and 3.6 meters thick. It has a total of 450 battlements, four gates in the east, west, north and south, and is equipped with gate towers. In addition to preventing wars, the ancient city wall of Danzhou also played an excellent role in protecting against floods. In 1902 during the Qing Dynasty, the ancient city wall blocked a devastating flood, saving the officials and people of Huaiyuan County from a devastating disaster.