The Great Wall is an ancient Chinese military defense project. It is a tall, strong and continuous wall to limit the movement of the enemy to ride. The Great Wall is not a single isolated wall, but a defense system that takes the wall as the main body and combines with a large number of cities, obstacles, pavilions, and symbols.
The history of building the Great Wall can be traced back to the Western Zhou dynasty. During the spring and autumn and warring states periods, the kingdoms contended for hegemony and defended each other. After qin destroyed the six kingdoms and unified the world, the first emperor of qin connected and repaired the warring states Great Wall. The Ming dynasty was the last dynasty to overhaul the Great Wall，and most of the Great Wall seen today was built at this time. Many great and thrilling battles took place here, and many changes of government were related to the gains and losses of retaining the Great Wall. This greatly enriched the cultural connotation of the Great Wall.
The Great Wall starts from Hushan mountain in Dandong, Liaoning province in the east, and ends at Jiayuguan Pass in Gansu province in the west. It passes through 10 provinces, regions and cities from east to west. The total length of the Great Wall is 8851.8 km, of which the length of the artificial wall is 6259.6 km, and the length of the moat and natural formation is 2592.2 km.
Thousands of laboring people in ancient China contributed their wisdom and sweat to it and made it one of the wonders of the world. This great building reflects the idea of a war of fortification at that time, and also marks the high achievement of architectural technology at that time.
