Temple of Heaven is part of a temple complex in Tiantan park and was built in 1406-1420. It was a sacred site where the emperor held religious ceremonies with elaborate music and offerings to communicate with heaven.
The processions began at the Circular Mound Altar (圜丘坛) . It is an empty circular platform on three levels of marble stones, each decorated by lavishly carved dragons. The center of the altar is a round slate and the sound of the prayer will be reflected by the guardrail into Heaven.
The Imperial Vault of Heaven (皇穹宇) is a single-gabled circular building, built on a single level of marble stone base. It is surrounded by the Echo Wall,that would transmit the music over large distances.
The Vermilion Steps Bridge, a 360-meter-long raised walkway that slowly ascends from the Vault to the Hall of Prayer.
The Hall of Prayer for Good Harvests (祈年殿) is a magnificent triple-gabled circular building, built on three levels of marble stone base and is completely wooden, with no nails. Earth was represented by a square and Heaven by a circle; with 4 beams symbolizing the connection of Heaven and Earth.
Now it is a public park where people can play cards and exercise.