Forbidden City’s Defense

The Forbidden City in Beijing was a place exclusively for the Emperor, his family, nobles, ministers, and heads of state. Thus, a moat and a high wall with four massive corner towers protected the largest palace complex in the world.

Reasons for Defense

The Forbidden City was so carefully built to keep out unwanted guests for many reasons.

The first main reason was to protect the emperor of China, and the emperor’s family. During the reign of imperial China, the seat of the emperor was hotly contested. Opportunistic sons had no problem killing off an emperor in order to get closer in succession to the throne. Additionally, nobles were fine targets for assassinations because of their immense fortunes and power to be inherited.

Even the foundation of the city is built with a system of stones laid crosswise on top of each other to prevent assassins from tunneling in beneath the city.

The second main reason for the defense was the monetary and civic value of the artifacts, items, and constructions within the forbidden city. Everything from fine silks and furs, jewels, gold, and even important seals and documents [that could sew chaos within the Chinese bureaucracy if stolen] were held in the forbidden city. Preventing theft of these items was alone enough reason for high security.

The Forbidden City was thus designed with four large watchtowers on each corner of its massive rectangular wall. Guards could keep a careful eye on the comings and goings of people from these towers. A moat circled the entirety of the city as well, with only four bridges crossing it- and each of the four bridges led to one of the only four entrances and exits to the enormous palace complex.

The Gates

The only entrances and exits to the city were the 4 gates on each side of the city, aligned with the cardinal directions. Two small side gates near the south end of the Forbidden City permitted entry and exit, and two large gates centered in the north and south walls were the main thresholds, with large central doors used exclusively by the emperor himself. Today, only the front and back gates are used by the thousands of tourists who visit every day. The front gate is used as the main entrance, while the back gate is the main exit.

The front gate is called the Meridian Gate, and it is built in the center of the South Wall, along the meridian axis, hence the name. The back gate is known as the Gate of the Primacy of Heaven, or the Gate of Divine Might, and is built in the center of the north wall of the forbidden city.

The Forbidden City Moat

The forbidden city’s moat circled the entire palace complex. The only crossings were at the two side gates, the Meridian Gate (the front gate), and the back gate. The palace moat was originally built in the Yuan dynasty (established by the Mongol leader Kublai Kahn officially in 1271, and lasting until 1368), like a moat and means of irrigation for the Yuan imperial palace. When the Ming Dynasty (1368-1644) built the modern-day Forbidden City, they diverted the same moat and irrigation water from the Yuan palace to perform the same function at their imperial palace.

The moat was built/re-engineered from the Yuan Palace to the Forbidden City in 1420, during the reign of Emperor Yongle (reigning from 1402-1424). The total length of the moat is 3800 meters long and 52 meters wide. Built with security in mind, both sides of the moat have steep embankments, making crossing without a bridge impossible.

The City Wall and Four Watchtowers

The whole complex is surrounded by an 8-meter-high stone brick wall that measures 3,430 meters total in length.

At each of the Forbidden City wall’s corners is a watchtower. Like most of the city, the wall and the construction of the watchtower were completed in 1420. The emperor asked the towers to be constructed with such complexity that the local artisans and carpenters were at a loss. A local legend states that the main foreman had all but given up on constructing the four towers within the deadline when he saw an old man selling grasshoppers in cages. The grasshopper cages had a smaller-scale version of exactly the type of architecture the emperor had requested. To this day, the watchtowers maintain their beautiful and complex construction, with columns, girders, and multi-eave roofs.

Back to the Forbidden City.