It is still the moon and border pass in Qin and Han dynasties, and the enemy has fought a protracted war. This fortress was built during the period of Wang Changling in the Tang Dynasty.
Flag-raising night robbery in the account, Hu Bing is short of nod. This fortress was crossed by Ma Dai in the Tang Dynasty.
Only the battlefields where countries die, why do they die in boots? This fortress was built in Xu Xilin in Qing Dynasty.