First built in 1420, then enlarged several times and now covered an area of 2,700,000 m² (four times bigger than the Forbidden City), the Temple of Heaven was the place where emperors of the Ming Dynasty (1368-1644) and Qing Dynasty (1644-1911) held the Heaven Worship Ceremony.

The temple is enclosed by a long wall, and separated by two walls, the inner altar and the outer altar. The northern part within the wall is semicircular symbolizing the heavens and the southern part is square symbolizing the earth. The northern part is higher than the southern part. This design shows that the heaven is high and the earth is low and the design reflected an ancient Chinese thought of ‘the heaven is round and the earth is square’.

The most magnificent buildings are the Circular Mound Altar (Huanqiutan, 寰丘坛), the Imperial Vault of Heaven (Huangqiongyu, 皇穹宇) and the Hall of Prayer for Good Harvest (Qiniandian, 祈年殿) from south to north. Regarded as the Son of Heaven, the emperors used the symbols everywhere

The Circular Mound Altar:  Built in 1530, it was the place where the emperor held the great ceremony of worshipping heaven. The Altar is an empty circular platform on three levels of marble stones, each of them has the balustrades carved with dragon pattern, and under each layer a stone dragon head is extended out, which is used for the drainage. When you shout or tap on the circular stone at the centre of the top level, the sound waves will be reflected off the nearby railings, creating a distinctive echo. In the Chinese Culture, Nine is the top of Yang, so the number Nine is represented in most of the emperors’ architectures, like this Altar. The number of columns and steps is 9 or 9 times everywhere. The top level has nine circles of fan-shaped stones. There are nine stones in the innermost circle, and nine more in each outer circle, and the same in the middle and lower levels. The number of the balustrades of three levels is respectively 72, 108 and 180, adding up to exactly 360.

The Imperial Vault of Heave is between the Circular Mound Altar and The Hall of Prayer for Good Harvest. The roof is laid with blue glazed tiles, symbolizing the blue sky. The main hall is supported by 16 columns, in the middle of which a round stone pedestal carved in white marble was dedicated to the “heaven god” tablet, stone tablets used in the harvest prayer ceremony. Both the main hall and the side hall are surrounded by a circular wall, which can transmit the sound wave regularly due to the surface smooth, that’s why it is called “echo wall”.

The Hall of Prayer for Good Harvest: First built in 1420, it is the earliest building in the temple. This building with three-tiered roof is completely wooden and without nails. It is supported by 28 large columns in three concentric circles who symbolize the twenty-eight constellations in Chinese cosmologies. The four ‘Dragon Columns’ in the center symbolize the four seasons, and the ‘12 Golden Columns’ in the middle circle symbolize the twelve months of a year, while the 12 ‘Giant columns’ in the outer circle symbolize the twelve hours of a day. The columns in the middle and the outer circles symbolize together the 24 solar terms in the Chinese calenderer.