The Forbidden City is the largest museum of ancient culture and art in China, located in the center of Beijing's central axis. Covering an area of about 720,000 square meters, the building area is about 6,543,800 square meters. It has more than 70 palaces and 9000 houses. The length of the Forbidden City is 96 1 meter from north to south and 753 meters from east to west. Surrounded by a wall with a height of 10 meter, there is a moat with a width of 52 meters outside. There are four gates in the Forbidden City, the Wumen Gate in the south, the Shenwu Gate in the north, the Donghua Gate in the east and the Xihua Gate in the west. There is a turret in every corner of the city wall, which has a complicated structure.