Located at the Summer Palace Royal Gardens northwest of Beijing, China, this doorway, was surrounded by tufa rock, a fresh water limestone formed by carbonate minerals. It was dredged from a fresh water lake to build one of the walls on the grounds of the summer palace. The grounds were a retreat for the royal families around 1750 and noted for its beautiful gardens.
The Empress dowager Cixi was known for embezzling navy funds to rebuild the grounds after a fire and attack. It was declared a Unesco World Heritage site in 1998.