Constructed from 1406 to 1420, the complex consists of 980 buildings and covers 72 hectares (over 180 acres). The palace exemplifies traditional Chinese palatial architecture, and has influenced cultural and architectural developments in East Asia and elsewhere. The Forbidden City was declared a World Heritage Site in 1987, and is listed by UNESCO as the largest collection of preserved ancient wooden structures in the world.
Since 1925 the Forbidden City has been under the charge of the Palace Museum, whose extensive collection of artwork and artefacts were built upon the imperial collections of the Ming and Qing dynasties. Part of the museum's former collection is now in the National Palace Museum in Taipei. Both museums descend from the same institution, but were split after the Chinese Civil War. Since 2012, the Forbidden City has seen an average of 15 million visitors annually, and had 16 million visitors in 2016.
The common English name "Forbidden City" is a translation of the Chinese name Zijin Cheng (Chinese: 紫禁城; pinyin: Zíjinchéng; literally: "Purple Forbidden City"). The name Zijin Cheng first formally appeared in 1576. Another English name of similar origin is "Forbidden Palace".
The name "Zijin Cheng" is a name with significance on many levels. Zi, or "Purple", refers to the North Star, which in ancient China was called the Ziwei Star, and in traditional Chinese astrology was the heavenly abode of the Celestial Emperor. The surrounding celestial region, the Ziwei Enclosure (Chinese: 紫微垣; pinyin: Zǐwēiyuán), was the realm of the Celestial Emperor and his family. The Forbidden City, as the residence of the terrestrial emperor, was its earthly counterpart. Jin, or "Forbidden", referred to the fact that no one could enter or leave the palace without the emperor's permission. Cheng means a city.
Today, the site is most commonly known in Chinese as Gùgōng (故宫), which means the "Former Palace". The museum which is based in these buildings is known as the "Palace Museum" (Chinese: 故宫博物院; pinyin: Gùgōng Bówùyùan).