Introduction to Jiayuguan Pass City: It is located in the middle of the narrowest valley of Jiayuguan Pass. The walls on both sides of the city pass cross the Gobi Desert. It is connected to the Black Mountain Hanging Wall to the north and the No. 1 pier in the world to the south. It is the westernmost pass of the Great Wall in the Ming Dynasty. Since ancient times, It is the first pass in Hexi and the most complete one among the many passes of the Great Wall.