Dajingmen is a very special gateway among the many passways of the Great Wall in China. Academia at home and abroad has been listed as important gateway as Shanhaiguan, Juyongguan and Jiayuguan. The gates of the Great Wall of China are called "gates" and "kous", and only Zhangjiakou is called "jingmen", which contains the charm of "business culture" and "wu culture", and also flows the historical origin of ethnic integration. Since Longqing 5 years ago, Zhangjiakou Dajingmen Yuanbaoshan area has gradually formed a border market known in history as "Gong City" and "Tea Horse Exchange City". Livestock, fur, medicinal materials, woolen goods, silverware, etc. from Mongolian grassland and the European hinterland were replaced here with silk, tea, porcelain and sugar, and the gate of Dajing became an inland port for international barter trade in northern China. The feudal dynasty, with the Great Wall and the Gate as the boundary, business foreigners can only trade outside the city. "Jingmen" means the border gate. In 1927, Gao Weiyue, the governor of Chahar, wrote the four big-faced characters "Dahao River and Mountain" on the gate of Dajingmen, which were strong and spectacular, and added charm to Dajingmen.