The Summer Palace is a large combination of lakes, gardens and palaces in the city, mainly on the Longevity Hill and Kunming Lake. The area covers approximately 2.9 km2, of which ¾ of it is water. The 2.2 km2 area of Kunming Lake was man-made and the excavated soil was used to build Longevity Hill. The origin of the palace was thought to be built during the Jin dynasty in 1153.
The design of the Summer Palace was based on one of the legends in Chinese mythology relating to the three divine mountains in the East Sea: Penglai, Fangzhang, and Yingzhou. The three islands in Kunming Lake were built to represent these three mountains.
The centre of the palace houses Great Temple of Gratitude and Longevity, where there is the 700 metres Long Corridor which furnished with artistic decorations.