Introduction to shade conditions: On the east side of Chengguang Hall, there stands an ancient pitch pine tree more than 20 meters high, with a scaly trunk with a circumference of 3.18 meters. The tree's posture is flat and strange, its shape is like an umbrella, its crown is round like a cover, and it is vigorous and straight. According to legend, it was planted in the Jin Dynasty and is now more than 800 years old. The ancient pine once provided shade and coolness to Qianlong. Qianlong imitated the story of Emperor Qin Shihuang's visit to Mount Tai and was granted the title of "Five Official Pines". The ancient pine on Tuancheng was granted the title of "Shade Marquis", which was the first of its kind for pine and cypress titles.