City walls, ancient military defense facilities, and military defense lines composed of city walls and other auxiliary military facilities. It also refers to the defensive barrier buildings built around Du Yi by the old farming people in response to the war, using materials such as civil and masonry.
The meaning of city wall can be divided into broad sense and narrow sense according to its function. Broadly speaking, the city wall is divided into two categories, one is the main part of the Great Wall, and the other belongs to the city (city) defense building, which consists of the city wall and ancillary facilities to form a closed area. In a narrow sense, a city wall refers to an enclosed area of a city consisting of a city wall and ancillary facilities. The enclosed area is in the city, and the enclosed area is outside the city.
Extended data:
Historical value of city wall
The city wall is the product of the development of human society to a certain stage, both at home and abroad. The extensive application and rich connotation of the ancient city wall in China are beyond the reach of other countries and nations in the world.
As far as application is concerned, in addition to the walls of the imperial city and the inner and outer cities of counties and counties, some altars and temples, tombs, gardens and temples belonging to royal buildings also adopt this kind of enclosure structure to varying degrees, which is very rare in other countries.
Secondly, the walled enclosure of a limited space (such as a city) has been greatly extended to a region or even the whole country, that is, the border town that began in the Spring and Autumn Period and the Warring States Period. From frontier fortifications between vassal states to the Great Wall of Wan Li, which runs through northern China and has a complete system.
Although similar walls were built in ancient Rome to resist barbarian invasion, the scale and time were not as big as those in China. Therefore, it can be said that the achievements of ancient China in this respect are outstanding and unparalleled in the world.
The existence and development of anything must have its reasonable connotation. All the city walls appear, first of all, because they can provide protection for closed spaces. In China, the change of consciousness caused by social development has given the earth-rock wall a new spiritual connotation.
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