Lantern viewing pole and small offering altars inside the outermost square wall
To the southwest of the altar stands a pole which was used to hang a cylindrical bamboo-woven lantern. It is 29 meters (95 feet) high. It has a lever and pulley for raising and lowering the lantern, which was lit for the starting and ending time of the worshipping ceremony. There were originally three poles.
An outdoor empty circular platform on three levels of marble stones, part of the Altar of Heaven (Temple of Heaven) complex, built during the 9th year of Emperor Jiajing's (Ming Shizong or Zhu Houcong) reign of the Ming Dynasty. Enlarged in 1749 (the 14th year of the Emperor Qianlong's reign of the Qing Dynasty). The round terrace was first covered with deep blue glazed slabs surrounded with a white marble balustrade when it was expanded. The round terraces represent communication with heaven. All the components of the terraces and balustrades are multiples of the number 9. During the Ming and Qing Dynasties, the emperors would offer sacrifices to Heaven on the day of the Winter Solstice every year. Sacrificial animals and other offerings were burned here to ensure good harvests.