Built in 1530, the 9th year of Emperor jiajing’s reign of the Ming dynasty, in a round shape with a double-eave roof, and named first the Hall for Appeasing Gods, it was the main hall of the Celestial Treasure House of the Circular Mound Altar, housing the Gods’ tablets to be used at the ceremony of worshipping Heaven. It was renamed the Imperial Vault of Heaven in 1538 and rebuilt into the present shape in 1752.
19.5 meters in height and 15.6 meters in diameter, the hall is a finely interlaced wooden structure with a blue tile roof crowned with a gilded sphere, looking elegant and majestic. It has a coffered ceiling with a bluish green design of a coiling gilded dragon playing with a pearl at the centre. It is indeed a masterpiece of ancient architecture of China.