Fifteen kilometers (9 miles) to the northwest of Beijing is the Summer Palace. Now a large park of 716 acres, it was formerly the imperial garden retreat from the summer heat of Beijing. Surrounding hills shelter the site, and the Kunming Lake provides a cooling effect. The site was used as an imperial park as early as the mid-12th century, and continued as an imperial garden in the Ming and Qing dynasties. In 1860 Anglo-French forces burned the site to the ground. It was reconstructed by the Empress Dowager Cixi in 1888, using funds that had been reserved for building a modern naval force. The large marble boat that sits immobile by the edge of the lake is an ironic reminder of the waste and mismanagement that led to the decline of the imperial state.