Beihai Park is located in the central area of Beijing, west of Jingshan Mountain and northwest of the Forbidden City. Known as the Three Seas together with China Sea and South China Sea, it is an ancient royal garden in China.

It was opened as early as Liao, Jin and Yuan Dynasties, and turned into a royal garden in Ming and Qing Dynasties. It is one of the oldest, most complete, most comprehensive and most representative royal gardens in China and the oldest preserved royal garden in China.