1, Great Wall National Defense Engineering System

The Great Wall, which stretches across Wan Li, is not only a single wall, but a complete defense engineering system composed of various fortifications such as the wall, watchtower, Guancheng, Dunbao, Yingcheng, Wei Shuo and Zhencheng beacon tower. This national defense engineering system is commanded and controlled by military command systems at all levels.

2. Construction of the Great Wall Defence Project.

Accumulated rich experience in the construction process of more than 2000 years. First of all, in terms of layout, when Qin Shihuang built the Great Wall in Wan Li, he summed up the test of "blocking the road because of dangerous terrain". This principle has been followed for more than two thousand years and has become an important basis for military deployment. Based on the principle of "using local materials and teaching students in accordance with their aptitude", many structural methods have been created.

3. The wall of the Great Wall

It is the main part of this defense project. It is built on steep mountains or plains, and it is built according to the needs of topography and defense function. All the places built in the plains or the key passes are very tall and strong, but in the steep mountainous areas, they are relatively low and narrow. In order to save manpower and cost, even some of the most steep places are not convenient to build, so the methods of "gable" and "splitting gable" are adopted.

Extended data:

The value of the Great Wall:

1, the Great Wall of Wan Li began in the Spring and Autumn Period and the Warring States Period, and accompanied the feudal society of China for more than two thousand years. As we all know, the ancient civilization in China has a long history, and the feudal society is the richest and most brilliant chapter. All the major political, economic, cultural and historical events in the feudal society have left their marks on the Great Wall.

2. As a historical site, the Great Wall places hydrology on the land of China. The Great Wall of Wan Li contains the splendid culture and art of the Chinese nation for more than 2,000 years, and its connotation is very rich. In addition to the architectural layout, modeling, sculpture and painting of the city wall, Guancheng, Zhencheng and beacon tower, there are also poems and songs, folk literature and opera rap.

References:

People's Network-World Cultural Heritage: The Great Wall