五珠球编法图

简介：But at that time, Ningyuan City was no longer a small town in the Xuanden year. Under the auspices and support of Sun Chengzong, the court invested a lot of manpower, money and food to expand Ningyuan into a brick-and-stone structure, divided into two inner and outer cities, with high forts built at the four corners. , protruding from the corner of the city, with red cannons mounted on it, and a solid fortress with complete defense facilities.