The Purple Mountain Observatory sits on the peak of Purple Mountain and affords great views over the surrounding countryside and the lakes below. The Observatory was built in 1934 and has since become one of the country's leading astrological bases. Thus, it occupies a very important position in the history of Chinese astronomy. Considered the cradle of modern Chinese astronomy, the observatory still keeps ancient astronomical instruments invented by the Chinese as a tribute to her forbearers. Much of the original equipment in the Observatory was destroyed or stolen during the Japanese invasion in 1937. Getting here involves a longer walk than most of the sights on the mountain, but it is peaceful and the air is fresh up here. 

Celestial Globe
Invented by Zhang Heng, an outstanding astronomer in the Eastern Han Dynasty (25 A.D.-220 A.D.), it was used to locate the position of celestial bodies and define their rotations. The one displayed here was made during the Qing Dynasty (1644- 1911). Measuring one meter in diameter, it is inlaid with 1449 stars, the ecliptic and the equator. 

Armillary Sphere
The invention of this instrument dates back to the Han Dynasty (206 B.C.-220 A.D.). It was used to locate celestial bodies and define their movements. The bronze one kept here was made in 1437 during the Ming Dynasty (1368-1644). 

Sundial
The bronze instrument was invented more than 3,000 years ago. It was used to define the 24 traditional Chinese solar terms and the length of the tropical year. The one on display was made in 1439. 

Altazimuth
The instrument, made at the end of the Qing Dynasty, was used to locate celestial bodies and determine their heights.