Introduction to the ancient city wall: The ancient city wall with a history of more than 600 years was built in the 14th year of Hongwu in the Ming Dynasty. Its shape is similar to the Badaling Great Wall. It is characterized by the creation of a classic "water city" that incorporates water sources and water energy into the defense system. . There are four towers in the "Water City", with a circumference of 4,700 meters, a height of 7 meters, and a width of 3 meters. At present, the east, west, south and north city gates have been completely preserved to this day.