The Xian City Wall is the best preserved, oldest and largest ancient city defence system in China. It is also one of the most important landmarks of the Xian city. The original foundation of the Xian City Wall was based on the ruins of the Imperial City Wall of Chang'an City--the capital of the Tang Dynasty. In 904 A.D. when the capital of the Tang Dynasty was moved eastward, the Governor-general Han Jian had the city renovated and turned it into an army garrison and named it 'New City'. Since then the city was used continuously by Song and Yuan Dynasties, and its features kept unchanged. The Ming Dynasty was set up in 1368 and the Ming army entered the city in 1369. Afterward the city was renamed as 'the Prefecture of Xian'.
History
At the time when Zhu Yuanzhang captured Huizhou, long before the establishment of the Ming Dynasty, he was admonished by a hermit named Zhu Sheng, who told him to "built high walls, store abundant provisions and take your time in proclaiming yourself emperor", advice which Zhu Yuanzhang heeded. Once the whole country was unified, he sent orders to the local governments to built city walls on a large scale. Zhu assumed that "out of all the mountains and rivers in the world, the central Qin is the most strongly fortified and strategically impregnable." The city wall of Xian is an extension of the old Tang Dynasty structure, as a result of this wall building campaign. Xian's city wall after its enlargement in the Ming Dynasty stands 12 meters high. It is 12-14 meters across the top, 15-18 meters thick at bottom and 13.7 kilometers in length.
The ramparts
There is a rampart every 120 meters. The ramparts are towers that extend out from the main wall, the top of the rampart being at the same level as the top of the wall. The ramparts were built to allow soldiers to see those enemies who would try to climb the wall. The distance between two ramparts is just within the range of arrow shot from either side. This allowed soldiers to protect the entire wall without exposing themselves to the enemy. They are altogether 98 of them on the wall; each has a sentry building on top of it.
The gates
Since the ancient weapons did not have the power to break through a wall and the only way for an enemy to enter the city was by attacking the gate of the city wall. This is why complicated gate structures were built within the wall. In Xian, the city wall includes four gates and they are respectively named as Changle (meaning eternal joy) in the east, Anding (harmony peace) in the west, Yongning (eternal peace) in the south and Anyuan (forever harmony) in the north. The south gate, Yongning, is the most beautifully decorated one. It is very near to the Bell Tower, center of the city. Important greeting ceremonies organized by the Provincial Government are usually held in the south gate square.
The gate towers
Each city gate has three gate towers: Zhenglou, Jianlou and Zhalou. The main tower is called Zhenglou. Zhalou is the gate tower with the suspense bridge, and Jianlou is the narrow tower. The Zhalou tower stands away from the wall. It is used to lift and lower the suspense bridge. The Jianlou tower is in the center of the others. Its front and the two outer sides have square windows to shoot arrows from. The Zhenglou tower is the inner one. It is the main entrance to the city. Jianlou and Zhenglou are connected by tunnels, called Wengcheng in which soldiers could be stationed. From the Wengcheng there are also horse passages leading to the top of the wall. These are gradually ascending steps made so that it is easy for war horses to ascend and descend. There are all together 11 horse passages around the city.
The watch towers
A watch tower is located on each of the four corners of the wall. The one at the southwestern corner is round, probably after the model of the imperial city wall of the Tang Dynasty, but the other three are square-shaped. On top of the watch towers there is a corner rampart, higher and larger than the ordinary ramparts. This shows the strategic importance of the corners of the city wall in war times.
Initially, the wall was built with layers of dirt, with the base layer including also lime and glutinous rice extract. Throughout the time Xian City Wall has been restored three times. In 1568, Zhang Zhi (the government officer of that period) was in charge to rebuild the wall with bricks. In 1781, another officer, Bi Yuan, refitted the city wall and the gate towers. More recently (since 1983) the Shaanxi Provincial Government restored the city wall again. A circular park has been built along the high wall and the deep moat. The thriving trees and flowers decorate the classical Chinese architecture of the wall, adding additional beauty to the city of Xian.