In 1540 El Morro, a fort that stands on a rocky peninsula controlling the entrance to San Juan Bay, was constructed due to continual attacks by both the English and the Dutch. By 1797, the complex design that can be seen today was completed. This historic site has been declared a World Heritage Site by the United Nations and the U.S. National Park Service. Control Point was contacted in 2013 to provide base documents to aid in preservation of the historic site.