City wall

The Xi'an City Wall is the largest and most well-preserved ancient city wall structure in China. It is a military defense system expanded on the basis of the imperial city of Chang'an in the Tang Dynasty and Fengyuan City in the Yuan Dynasty in the early Ming Dynasty. It is not only a landmark of Xi'an, but also an important material witness for studying the layout, military defense, and architectural art of ancient Chinese cities.

Overall shape and structure:
It is shaped like a closed rectangle, with a perimeter of approximately 13.74 kilometers.
Standing at a height of 12 meters, with a top width ranging from 12 to 14 meters and a base width spanning from 15 to 18 meters, its thickness exceeds its height, making it as sturdy as a mountain.
The wall is made of rammed earth at its core, with blue bricks on the outside and an earthen ramp ("haiman") on the inside for easy climbing.
Defensive system:
City Gates: Originally, there were four main gates (Changle, Yongning, Anding, and Anyuan). After the Republic of China, several additional gates were built, bringing the total to 18. Each main gate originally had three layers of defense: the gate tower, the arrow tower, and the main building.
Turret: Each of the four corners is equipped with a turret (currently only the southwest corner platform remains).
Enemy watchtowers (Mamian): There are a total of 98 enemy watchtowers protruding from the outer side of the city wall, designed for flanking and shooting at attacking enemies.
Crenels: There are 5,984 crenels (battlements) on the outer side of the wall top, used for observation and shooting.
Moat: Surrounding the city wall, it is 18 meters wide and 6 meters deep, forming the first line of defense.