To build a city wall is to build a city wall with bricks. In early ancient times, city walls were built of rammed earth. Later, with the development, the city walls were built with bricks.

During the Ming Dynasty, when the country was developed and the economy was prosperous, it became common to build city walls with bricks. The outer skin of city walls all over the country is covered with bricks, which is called brick city walls.

Wall bricks are wider and longer than bricks used for building houses. Wall bricks are made of white mortar. For all brick walls, the skin is made of brick, the foundation is made of stone strips, and the height of stone strips is not equal. Brick wall should be built on the top of the stone fence, and when the brick wall is built to a certain height, crib mouth and wall hole should be made.

Architectural history of city walls

In the early primitive society of China, the wall ramming technology was relatively rough. Specifically, the thickness of the rammed layer (generally about 10 cm thick, the maximum thickness can reach 30 cm) is uneven, the rammed layer is not dense enough, and sometimes the simple stacking form is adopted, so the firmness of the wall is poor.

The technology of fortification developed greatly in the Zhou Dynasty. At this time, the thickness of rammed layer has been reduced to 8 ~ 10 cm, which is very uniform and widely used in plate building form. The slope inside the wall also changes from gentle to steep (the angle is about 1.4).

With the vigorous development of brick-making industry in Ming Dynasty, ceramic bricks were widely used in various buildings. Almost all the existing brick walls were built in the Ming Dynasty, especially after the middle period. Although most of these city walls are brick on both sides and filled in the middle.