It is recommended that Yulin must go to scenic spots. Yulin is the seat of Suibian Town, a nine-sided town that refused Mongolia in the north of Ming Dynasty. Zhenbeitai is known as the first Great Wall, as well as Jiayuguan and Shanhaiguan. Unfortunately, few people know it. Walking on the cold wall, the eyes are full of flying flags, unexpectedly there is "Feng goes to the building empty River to flow by itself" sadness. At that time, there should be many generals here, but now only Xintianyou, which echoes in the scenic area, is accompanied. Walking around the four-storey city wall, the distant Maowusu desert is full of vigor and vitality. Last year, I strolled along the wall of Datong, another important town on nine sides, and I felt the same way. Why does the Great Wall always arouse strong emotions in the heart?