The garden of Prince Gong's Mansion is regarded as one of Beijing's most spectactular gardens. According to the guidebook I used in Beijing, Prince Gong, was the sixth son of the Guangxu emperor. However, according to Ben (see comment below), he was rather the sixth son of the Daoguang Emperor (1782-1850). His comment is supported by a biography on Nationmaster.com which adds that Prince Gong's "mother was the concubine of the third rank Jing (1812-1855), who later became Concubine Dowager Kangci, and was made posthumously Empress Xiaojing Cheng. She was the daughter of a Mongol official in the government, from the Borjigid clan (the descendants of Genghis Khan). The Daoguang Emperor (September 16, 1782 - February 25, 1850) was the seventh emperor of the Manchu Qing dynasty, and the sixth Qing emperor to rule over China, from 1820 to 1850."