Many times to Dajingmen, all in spring, summer and autumn, the first snow after visiting Dajingmen. After the snow, Dajingmen is dressed in silver, rich in layers, the Great Wall is beautiful, and the scenery is spectacular. Dajingmen, the key cultural relics protection unit in the country. Located at the north end of Qiaoxi District, Zhangjiakou City, it was built in Chonghui in 17 years (1644 AD) and has a history of more than 350 years. Dajingmen is one of the four major gates of the Great Wall of China, and has an important position in history. Dajingmen is a very special gateway among the many passways of the Great Wall of China. Academics at home and abroad have been listed as important 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 major characters of "Dahao River and Mountain" on the gate of Dajingmen. War and peace, life and death, prosperity and desolation, here are repeated and interpreted in succession. Dajingmen has experienced many vicissitudes and is a witness to Zhangjiakou's history. Many important historical events are closely related to Dajingmen. Dajingmen witnessed the poverty and weakness of the old China, and also witnessed the prosperity of the new China and the historical changes of Zhangjiakou. Zhangjiakou people are proud of Dajingmen, and Dajingmen have naturally become a symbol of Zhangjiakou.