This observatory, 15 km southeast of Dengfeng(South of Zhengzhou) within the Zhougong Miao temple complex, is the oldest surviving observatory in China. An observatory was built here in  the Zhou Dynasty.

The astronomer Guo Shoujing (1231-1314) designed this particular observatory in 1276, at the beginning of the Yuan period. The building is an angular construction made of brick and stone and stands 9.46 m high. A 31.9-m-long stone rod stretches out in front of the building and is used to measure the sun’s shadow. Based upon his own diagrams and with the aid of information collected by other observatories, Guo Shoujing worked out a calendar which corresponds to the present-day Gregorian calendar. A calculation that he made of the amount of time that it takes the earth to revolve around the sun was off by only 26 seconds.