Simatai Great Wall in the reign of emperor Hongwu

In the eleventh year of the reign of Emperor Hongwu, the emperor ordered Xu Da to build the Gubeikou Pass, and boost defense capability by adding stones on the prior Great Wall. Frontier fortress facilities such as passes, large and small gateways and beacon towers, and two gates are built, one is located at the Great Wall gateway, called "Tiemenguan Pass", which can only be passed by one ride and one car; One gate is located on the Chaohe River, which is called "Watergate Pass" and the ruins are still there.
Beginning in the early Ming Dynasty (AD 1368), the focus was on building passes and setting up stations to settle and defend the border. Piers and abutments are also built along the border. In the tenth year of Hongzhi in Ming Dynasty (1427), Prince Tatar led his troops to invade Gubeikou. Because of the strong defense of the Ming army, the invaders retreated.