Set in its own large and tranquil park about 2km south of Tian'anmen along Qianmen Dajie, the Temple of Heaven (daily 6am–6pm; ￥30, students ￥0.5), is widely regarded as the high point of Ming design. For five centuries it was at the very heart of imperial ceremony and symbolism, and its architectural unity and beauty remain for most modern visitors more appealing – and on a much more accessible scale – than the Forbidden City. There are various bus routes to Tiantan: bus #36 runs from Tian'anmen past the west and south gates, while #20 and #54 pass the west gate on their way from Beijing Zhan down to Yongdingmen, also via Tian'anmen, and bus #41 from Chongwenmen stops opposite the east gate.

The temple was begun during the reign of Emperor Yongle and completed in 1420. It was conceived as the prime meeting point of Earth and Heaven, and symbols of the two are integral to its plan. Heaven was considered round, and Earth square, thus the round temples and altars stand on square bases, while the whole park has the shape of a semicircle sitting beside a square. The intermediary between Earth and Heaven was of course the Son of Heaven, the emperor, and the temple was the site of the most important ceremony of the imperial court calendar, when the emperor prayed for the year's harvests at the winter solstice. Purified by three days of fasting, he made his way to the park on the day before the solstice, accompanied by his court in all its panoply. On arrival, he would meditate in the Imperial Vault, ritually conversing with the gods on the details of government, before spending the night in the Hall of Prayer of Good Harvests. The following day, amid exact and numerological ritual, the emperor performed sacrifices before the Throne of Heaven at the Round Altar.

It was forbidden for the commoners of old Beijing to catch a glimpse of the great annual procession to the temple and they were obliged to bolt their windows and remain, in silence, indoors. The Tiantan complex remained sacrosanct until it was thrown open to the people on the first Chinese National Day of the Republic in October 1912. Two years after this, the infamous General Yuan Shikai performed the solstice ceremonies himself, as part of his attempt to be proclaimed emperor. He died before the year was out.