After Qin unified the six countries in 22 1 BC, Qin Shihuang built the Great Wall in the north on a large scale in 32 years (2 1 BC) in order to defend the Huns. One kilometer to the west of Hongqi Store in Ubulangkou, Urad Middle Banner, Bayannur League, there is a collapsed Great Wall. As can be seen from the cross section, there is a neat wall inside the stone wall. According to textual research, this is the Qin Changcheng formed by Qin using Zhao Great Wall, heightening and widening it for maintenance.

Near the Great Wall, every 0.5 ~ 1.5 km, there are 1 high stone piles. From these collapsed stone piles, the original surrounding walls can also be found. According to the remaining part, the wall is about 5 ~ 7 meters long and 6 ~ 8 meters high. This is the beacon tower used as a warning signal on the Great Wall Line. Beacon towers are mostly located at the top of the mountain, with a wide field of vision, and the vertical distance from the Great Wall is generally no more than three kilometers. There are often houses on the highlands not far from the beacon tower. In important mountain passes and passes, there are often small town barriers, which are military castles attached to the Great Wall.