The Temple of Heaven, literally the Altar of Heaven (Traditional Chinese: 天壇; Simplified Chinese: 天坛; Pinyin: Tiān Tán) is situated in south eastern urban Beijing, in Xuanwu District. Construction of the Temple began in 1420, and was thereafter visited by all subsequent Emperors of the Ming and Qing Dynasties.

The Temple grounds covers 2.73 km² of parkland, and comprises three main groups of constructions, all built according to strict philosophical requirements:

• The Earthly Mount (圜丘坛), an empty platform on three levels of marble stones, where the Emperor prayed for favourable weather;
• The House of Heavenly Lord (皇穹宇), a single-gabled circular building, built on a single level of marble stone base, where the altars were housed when not in use;
• The Hall of Annual Prayer (祈年殿), a magnificent triple-gabled circular building, built on three levels of marble stone base, where the Emperor prayed for good harvests.

In ancient China, the emperor was regarded as the "Son of Heaven", who administered earthly matters on behalf of, and representing, heavenly authority. To be seen to be showing respect to the source of his authority, in the form of sacrifices to heaven, was extremely important. The temple was built for these ceremonies, mostly comprised of prayers for good harvests.

Each winter solstice the Emperor and all his retinue would move through the city to encamp within the complex, wearing special robes and abstaining from eating meat; there the Emperor would personally pray to Heaven for good harvests. The ceremony had to be perfectly completed; it was widely held that the smallest of mistakes would constitute a bad omen for the whole nation in the coming year.

The Temple of Heaven is the grandest of the four great temples located in Beijing. The other prominent temples include The Temple of Sun in the east (日坛), The Temple of Earth in the north (地坛), and The Temple of Moon in the west (月坛).

The Temple of Heaven was registered on the UNESCO's World Heritage List in 1998.

Facts and figures

• The Temple is surrounded by two cordons of walls; the outer wall has a taller, semi-circular northern end, representing the Heaven, and a shorter, rectangular southern end, representing the Earth.

• All the buildings within the Temple have special dark blue roof tiles, again representing the Heaven.

• The Altar of Heaven was constructed with details representing the number nine, the representative number of the Emperor. If you stand at the centre of the platform and clap your hands, you can hear the echo.

• The House of Heavenly Lord is surrounded by a curved wall, 6 metres tall and 32.5 metres in radius. It is nicknamed the 'Echo Wall' because a person at one end of the wall can hear the voice of a person at the other end of the wall.

• The Hall of Annual Prayer is 32 metres in diameter and 38 metres tall. It has four inner, twelve middle and twelve outer pillars, representing the four seasons, twelve months and twelve traditional Chinese hours respectively.