>> The Temple of Heaven was constructed from 1406 to 1420 during the reign of the Yongle Emperor

The Temple of Heaven is a medieval complex of religious buildings situated in the southeastern part of central Beijing. The complex was visited by the Emperors of the Ming and Qing dynasties for annual ceremonies of prayer to Heaven for good harvest. It has been regarded as a Taoist temple, although Chinese heaven worship, especially by the reigning monarch of the day, predates Taoism.

The temple complex was constructed from 1406 to 1420 during the reign of the Yongle Emperor, who was also responsible for the construction of the Forbidden City in Beijing. The complex was extended and renamed Temple of Heaven during the reign of the Jiajing Emperor in the 16th century. Jiajing also built three other prominent temples in Beijing, the Temple of Sun (日壇) in the east, the Temple of Earth (地壇) in the north, and the Temple of Moon (月壇) in the west. The Temple of Heaven was renovated in the 18th century under the Qianlong Emperor. By then, the state budget was insufficient, so this was the last large-scale renovation of the temple complex in imperial times.

The temple was occupied by the Anglo-French Alliance during the Second Opium War. In 1900, during the Boxer Rebellion, the Eight Nation Alliance occupied the temple complex and turned it into the force's temporary command in Beijing, which lasted for one year. The occupation desecrated the temple and resulted in serious damage to the building complex and the garden. Robberies of temple artifacts by the Alliance were also reported.[citation needed] With the downfall of the Qing, the temple complex was left un-managed. The neglect of the temple complex led to the collapse of several halls in the following years.

In 1914, Yuan Shikai, then President of the Republic of China, performed a Ming prayer ceremony at the temple, as part of an effort to have himself declared Emperor of China. In 1918 the temple was turned into a park and for the first time open to the public.

Inside the Hall of Prayer for Good Harvests.

The Temple of Heaven was inscribed as a UNESCO World Heritage Site in 1998 and was described as "a masterpiece of architecture and landscape design which simply and graphically illustrates a cosmogony of great importance for the evolution of one of the world’s great civilizations..." as the "symbolic layout and design of the Temple of Heaven had a profound influence on architecture and planning in the Far East over many centuries."

Symbolism 
A richly decorated interior in red, blue, green and gold with many intricate designs, rising to a ceiling above the upper bound of the image Earth was represented by a square and Heaven by a circle; several features of the temple complex symbolize the connection of Heaven and Earth, of circle and square. The whole temple complex is surrounded by two cordons of walls; the outer wall has a taller, semi-circular northern end, representing Heaven, and a shorter, rectangular southern end, representing the Earth. Both the Hall of Prayer for Good Harvests and the Circular Mound Altar are round, each standing on a square yard, again representing Heaven and Earth.

Panorama with the Hall of Prayer for Good Harvests in the center, viewed from the south

The number nine represents the Emperor and is evident in the design of the Circular Mound Altar: a single round marmor plate is surrounded by a ring of nine plates, then a ring of 18 plates, and so on for a total of nine surrounding rings, the outermost having 9×9 plates. The Hall of Prayer for Good Harvests has four inner, twelve middle and twelve outer pillars, representing the four seasons, twelve months and twelve traditional Chinese hours respectively. Combined together, the twelve middle and twelve outer pillars represent the traditional solar term.

All the buildings within the Temple have special dark blue roof tiles, representing the Heaven. The Seven-Star Stone Group, east of the Hall of Prayer for Good Harvest, represents the seven peaks of Taishan Mountain, a place of Heaven worship in classical China. There are four main supportive, dragon pillars each representing a season. The structure, held up by these dragons, imitates the style of an ancient Chinese royal palace. Twelve inner pillars symbolize the lunar months, and it is thought that the twelve outer pillars refer to the 12 two-hour periods of the day.
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