Located in Shanxi Province, Zhangbi Ancient Castle is a really cool underground fortress. Its history reaches back over 1,400 years. This special place mixes old military defense things, underground tunnels, and traditional buildings from the Ming and Qing dynasties. Because of this, it has turned into one of China's most interesting historical heritages. People often call Zhangbi Ancient Castle "China's Underground Great Wall". And it gives people a rare chance to know a lot about ancient war strategies and village life.
The most noticeable feature of Zhangbi Castle is its large underground tunnel network. It can stretch as far as 10,000 meters. People built this network during the Sui and Tang Dynasties. They used it for military defense and to escape. The tunnels have three levels. They have hidden ways, rooms for storing things, holes for watching, and trapdoors. Some parts are big enough for soldiers, but other parts are narrow ways to get away. Tourists can look around part of this complex building. Then they can better know how ancient soldiers moved secretly under the ground.
People designed Zhangbi Castle carefully. It can be seen as a very strong fortress. It has strong stone walls, towers for watching, and city gates that are well-protected. The South Gate (Zhengyang Gate) is the main way in. Twin towers are on both sides of it. These towers give good places to look out. The streets in the castle are winding. People built them on purpose to make invaders confused. The hidden places for archers let the people defending the castle launch sudden attacks. This design shows the advanced military building skills in ancient China.
Zhangbi has military architecture. Besides that, it also has temples that are well-kept and traditional residential courtyards. Among them, the Kongwang Temple is the most famous. There are some rare Ming Dynasty murals in the temple. These murals show Buddhist and Taoist figures. Next to the Kongwang Temple are traditional Shanxi-style houses. They have gray brick walls and nice wooden carvings. From these houses, people can know a little about the daily lives of the people who lived there before. The mix of military and civilian buildings makes Zhangbi special.
The Stargazing Tower is at the highest place of the ancient castle. People believe it was an ancient astronomical observatory. Experts believe that during the war, it was used for military divination and working out the calendar. Tourists are able to climb to the top of the Stargazing Tower. They can enjoy the amazing full views of the valleys around. This makes it a great place for taking photos, especially when the sun is setting.