1563, Jizhong Town starts from Shanhaiguan, and ends about 2. 1km south of Juyongguan, which is divided into 10 road. The first 7 roads belong to Jizhong Town, and the eighth to tenth roads are huanghua town, Juyongguan and Zhenbian Town. In this way, all the defense parts of Changping Town were merged into Yuji Town.

1568, Qi Jiguang took Ji Liao, the prime minister of Zuodu, to ensure the training affairs, control the general staff of the four towns and Jizhen, and divide the 10 road into 12 road, so it is also correct for the west boundary of Jizhen to reach the border town.

As for what Qi Jiguang himself said, "mountains and seas are left, towns are right", we can see the importance of Jiyun Town. The mountains and seas are left to Xiongguan, and the city and fortress are occupied in the west. It is not a specific expression of the town defense border, but even the town defense border can be expressed, because the town defense border town belongs to the defense system of Juyongguan.