Xi’an City Wall, also known as the Ming City Wall of Xi’an, is the largest and best-preserved ancient city wall in China. Many people come to Xi’an to visit the wall, but do not really know it. In fact, there are many unknown facts about the Xi’an City Wall.
1. One of the Four Corners of the Xi’an City Wall is in Round Shape
The northeast, southeast and northwest corner towers of Xi’an City Wall are square, but only the southwest corner tower is round, why?
According to the Ming Records, when Zhu Yuanzhang sent Zhu Hui to Xi’an to build the wall, most of the west and south sides of the Xi’an city wall were built along the old site of the Tang Imperial City, and the southwest corner of the city wall happened to have a round foundation, so it was directly used, so we see the other three corners of the Ming city wall in Xi’an today are square, only the southwest corner of the city wall is round.
2. The Thickness of the Xi’an City Wall is Greater Than the Height of the Xi’an City Wall
The height of the ancient city wall of Xi’an is 12 meters, but the thickness of the top of the Xi’an city wall is 12-14 meters and the thickness of the bottom is 15-18 meters, and the whole wall is trapezoidal, so the average thickness of the Xi’an city wall is greater than its height. Because the Xi’an city wall was an ancient strategic defense system, the thickness was greater than the height, and it was as solid as a mountain.
3. The Thickness of City Wall Corner Reaches More Than 35 Meters

The wall is 12 meters high, 12-14 meters wide at the top and 15-18 meters wide at the bottom, with a closed rectangle outline, 13.74 kilometers in circumference and a trapezoid cross-section, and the thickness of the corner of the wall from top to bottom is 16.97-25.46 meters according to the Pythagorean theorem.
However, there is also a corner platform at each of the four corners of the Xi’an city wall, and the projection of the corner platform can be calculated according to 11 meters according to the information shown online, so the final calculation shows that the thickness of the corner of the city wall is 30.41-35.46 meters.
4. 99 Layers of Bricks Were Built from Bottom to Top of the Outer Wall of the Xi’an City Wall
The outer wall of the Ming City of Xi’an was built from the bottom to the top with 99 layers of bricks. Ninety-nine and nine are both considered by the ancient Chinese to be “extreme numbers”. As a defensive project, the city walls were built to be high. If you are at the top, you can suppress the enemy. In The Art of War, Sun Tzu describes the power of the army as moving “above the nine heavens”.
5. 26 Million Bricks Were Used for the Construction of the City Wall
The size of the wall bricks is 45 cm long, 23 cm wide and 10 cm thick. According to statistics, more than 26 million bricks were used to build the wall, and if these bricks were connected, it would take five round trips from Xi’an to Shanghai.
6. The Entire Defense System of the Xi’an City Wall Has 10 Main Buildings
① Main Building
On the four gates of Xi’an in the Ming and Qing dynasties, there is a tall and magnificent two-story, three-eaves hutted gate tower, which is built on top of the main city wall gate, so it is the four gates main tower.

② Gate Tower
The gate tower is a building built on the frontal gate opening, named because it controls the “gate” drawbridge of the moat that must be passed into the city.
③Arrow tower
On the outside of the archery tower, the part above the wall is the eaves wall of the archery tower, and the top of the eaves wall, where it meets with the square, flattens out a layer of brick eaves, as a transitional decoration. The brick eaves are about 10 cm long. The outer gable wall of the archery tower is equipped with dense cut windows for a defensive counterattack.
④ Urn City
An urn city is a small semi-circular or square gate guard built outside the city gate (there are also special cases on the inside of the gate) to strengthen the defense of a castle or pass and is part of the ancient Chinese city walls.
⑤ Horse trail
The horse path is a ramp built for the cavalry and infantry to go up and down the city wall in ancient times.
⑥ Corner Tower
The corner tower is a building built on the corner platform, which is an important facility of the defensive engineering of the city wall. It is convex to the outer wall of the city wall, and the view from the tower is wide enough to observe the enemy clearly.
⑦ Battlements
Battlements are the gaps between the battlements along the top of the city wall. The gap of 0.6m between two battlements on the battlements of Ming Xi’an City is known as the battlements, which were set up for lookout and shooting, and are the defensive engineering facilities of the city wall, and there are 5984 battlements in the whole city.
⑧ Parapet Wall
Parapet wall refers to the thin retaining wall built on the inner and outer edges of the top of the city wall. Compared with the large city, it is extremely small, so it is called the parapet wall. Parapet wall built on the inner edge of the top of the city is also called Yu wall, built on the outer edge of the top of the city is also called the battlement wall. The parapet wall is used for the protection of the top of the city and the barrier against the enemy, and is a traditional defense building necessary for ancient city walls.
⑨ Enemy Tower
When you climb the Ming City Wall of Xi’an, you will find that on the outside of the tall wall, at certain intervals, there is a section that protrudes from the outside of the wall, which is the horse face (or called the enemy platform, pier platform, wall platform). There are two kinds of rectangular and semi-circular planes, which are named because of their long and narrow appearance like horse faces. The use of horse face is to interact with the wall, eliminate the dead angle under the city, and attack the enemy from top to bottom from three sides.
⑩Plasterwork
The plasterwork is the flat surface of the top of the city wall.