The Summer Palace （Yiheyuan） is mainly dominated by Longevity Hill（Wanshoushan， 60 meters high） and the Kunming Lake. It covers an expanse of 2.9 square kilometers, three quarters of which is water. The central Kunming Lake covering 2.2 square kilometers and it is divided into few parts by West Dyke. It was entirely man made and the excavated soil was used to build Longevity Hill. In its compact 70,000 square meters of building space, one finds a variety of palaces, gardens, and other classical-style architectural structures.
The Summer Palace （Yiheyuan）started out life as the Garden of Clear Ripples（Qingyiyuan） in 1750 (Reign Year 15 of Emperor Qianlong). Artisans reproduced the garden architecture styles of various palaces in China. Kunming Lake was created by extending an existing body of water to imitate the West Lake in Hangzhou. The palace complex suffered two major attacks--during the Anglo-French allied invasion of 1860 (with the Old Summer Palace also ransacked at the same time), and during the Boxer Rebellion, in an attack by the eight allied powers in 1900. The garden survived and was rebuilt in 1886 and 1902. In 1888, it was given the current name, Yiheyuan. It served as a summer resort for Empress Dowager Cixi, who diverted 30 million taels of silver, said to be originally designated for the Chinese navy, into the reconstruction and enlargement of the Summer Palace.
The cache near The West Causeway (XIdi). The West Causeway is modeled on the Su Causeway of the West lake in Hangzhou. From north to south the causeway is connected by six bridges, each is style: Lake-Dividing Bridge, Pastoral Poems Bridge, Jade Belt Bridge, Mirror Bridge, Silk Bridge and Willow Bridge. Between the Silk Bridge and the Willow Bridge there also have the Pavilion of Bright Scenery. Willow and peach trees were planted on the couseway and also have 19 mulberry trees that every over 300 years old。