The Temple of Heaven is the grandest cult architecture complex in the world and a masterpiece of the Chinese people created in ancient times. It covers 2,700,000 square meters (667 acres), which is nearly four times the area of the Forbidden City. The temple was constructed in 1420 during the Ming Dynasty (1368-1644), and was enlarged during the Qing Dynasty (1644-1911). Emperors of the two dynasties used to worship the heaven and pray for rich harvests, as the feudal emperors thought they were the son of the heaven.
This complex has two parts: the inner temple and the outer temple and is surrounded by two high walls. The two walls are elaborately constructed: the north section of walls is semicircular while the south section is square. This layout of walls reflects the ancient Chinese concept of the cosmogony: the sky is round and the earth is square. The primary buildings in the temple are the Altar of Prayer for Good Harvests in the north and Circular Mound Altar in the south. They are lined in the central axis of the whole temple and connected by a 36-meter-long bridge. Subsidiary buildings include Imperial Vault of Heaven, the Hall of Abstinence, a Bell Tower and relatively small halls.