The Forbidden City is the world's largest surviving palace complex and covers 72 ha. It is a rectangle 961 metres (3,150 ft) from north to south and 753 metres (2,470 ft) from east to west. It consists of 980 surviving buildings with 8,707 bays of rooms. The Forbidden City was designed to be the centre of the ancient, walled city of Beijing. It is enclosed in a larger, walled area called the Imperial City. The Imperial City is, in turn, enclosed by the Inner City; to its south lies the Outer City.
The Forbidden City remains important in the civic scheme of Beijing. The central north-south axis remains the central axis of Beijing. This axis extends to the south through Tiananmen gate to Tiananmen Square, the ceremonial centre of the People's Republic of China. To the north, it extends through the Bell and Drum Towers to Yongdingmen. This axis is not exactly aligned north-south, but is tilted by slightly more than two degrees. Researchers now believe that the axis was designed in the Yuan Dynasty to be aligned with Xanadu, the other capital of their empire.