About two kilometers southeast to the Xiangshan Park at the foot of the West Hill in Beijing, the Tuan Chen Fortress was first built in the 14th year (1749) of Emperor Qianlong's reign. Being the only one of its kind, the Tuan Chen Fortress is a castle-like military training compound for emperors of the Qing Dynasty (1644-1911) to train and inspect their troops.

The layout of the Tuan Cheng Fortress has a style of its own, with a great spectacle. From north to south are, in turn, Tuan Cheng, the drill hall, the drill ground, the Shisheng Temple Stele Pavilion, and the Pine Hall. The drill hall is a circular castle-like building, enclosed by a city moat. Two white marble bridges are over the moat, facing the city gate. The south and north side of the castle has respectively a gate with a tablet hung on it -- the north tablet reads Zhi Yu Jin Tang (will strong as the impregnable fortress), and the south one reads Wei Xuan Bi Lei (power running over rampart). Inside the castle, a circular yard measuring 1,800 square meters is in the center, with two paths for horse running up the east and west city walls to the top of the fortress. On the south and north gates are two towers of the same specifications. The south city gate tower has turned into a temporary exhibition hall, displaying historical materials of the Tuan Cheng Fortress, copies of imperial couches, battle-axes, gongs, umbrellas, fans and weapons of the Qianlong reign according to their original shape, which gives visitors a brief introduction of relevant historical facts and the development of the Tuan Chen Fortress.

A drill ground named the Peach Garden is situated to the south of the drill hall. It is said that in the twelfth year (1747) of Qianlong's reign, Sichuan ran into chaos caused by war, with local people setting up watchtowers in every strategic pass to resist the garrison of the Qing troops. To calm down the turmoil and preparing soldiers for battle against heavily armed defenders fortified in watchtowers, Emperor Qianlong duplicated several watchtowers in the Tuan Cheng Fortress and trained a special troop named Smart Scaling Ladder Troop. Later, the Tuan Cheng Fortress became the drill place of Scaling Ladder Troop and was inspected by Emperor Qianlong from time to time. The Stele Pavilion of Shisheng Temple was built to the southwest of the drill hall, with a tablet erected in the center. Inscribed by Emperor Qianlong himself and written in languages of the Han, Manchu, Mongolian and Zang, the inscriptions on the tablet recorded the cracking down of Sichuan turmoil and the development of Shisheng Temple.

Featuring a special architectural style, the Tuan Cheng Fortress is Beijing's only military training center combining city, temple, tower and drill ground into a whole set. In ancient times, emperors of past dynasties rewarded soldiers here. Nowadays, Tuan Chen has held three large martial art events, and received many martial art fans from all over the country.