Inside includes Longevity Hill (万寿山; 萬壽山; Wànshòu Shān) Kunming Lake and Seventeen Hole Bridge.

The central Kunming Lake, covering 2.2 square kilometres (540 acres), was entirely man-made and the excavated soil was used to build Longevity Hill.

The Summer Palace, which is inspired by the gardens of South China, contains over 3,000 Chinese ancient buildings that house a collection of over 40,000 valuable historical relics from various dynasties.

The natural landscape of hills and open water is combined with artificial features such as pavilions, halls, palaces, temples and bridges to form a harmonious ensemble of outstanding aesthetic value".

At the beginning of the reign of the Qianlong Emperor (r. 1735-1796), many imperial gardens were built in the area around present-day Beijing's Haidian District and accordingly, water consumption increased tremendously.

Around 1749, the Qianlong Emperor decided to build a palace in the vicinity of Jar Hill and the Western Lake to celebrate the 60th birthday of his mother, Empress Dowager Chongqing.

The Summer Palace, whose construction was completed in 1764 at a cost of over 4.8 million silver taels, was initially named "Qingyiyuan" (清漪園; 'Gardens of Clear Ripples"').

The design of the Summer Palace was based on a legend in Chinese mythology about three divine mountains in the East Sea, namely Penglai, Fangzhang (方丈) and Yingzhou (瀛洲).

As the palace was not equipped with facilities for long-term residence and the daily administration of state affairs, the Qianlong Emperor never dwelt there and only remained for the day whenever he visited it.

As the Qing Empire started declining after the reign of the Daoguang Emperor (r. 1820–1850), the Summer Palace gradually became more neglected and the architectural features on the three islands were ordered to be dismantled because the costs of maintenance were too high.

The occupations came as part of an invasion of Northern China by Britain and France to force the government of the Qing dynasty to come to the negotiating table.

Between 1884–95, during the reign of the Guangxu Emperor (r. 1875–1908), Empress Dowager Cixi reportedly ordered up to 22 million silver taels,[4] originally designated for upgrading the Qing navy (the Beiyang Fleet), to be used for reconstructing and enlarging the Summer Palace to celebrate her 60th birthday; however, some other sources state that a maximum of six million taels were allotted, of which none came from the Navy's capital budget, but only the accrued bank interest paid.

In 1924, after Puyi was expelled from the Forbidden City by the warlord Feng Yuxiang, the Beijing municipal government took charge of administering the Summer Palace and turned it into a public park.