The Golden Gate National Recreation Area (GGNRA) is a U.S. National Recreation Area protecting of ecologically and historically significant landscapes surrounding the San Francisco Bay Area. Much of the park is land formerly used by the United States Army. GGNRA is managed by the National Park Service and is one of the most visited units of the National Park system in the United States, with more than 15 million visitors a year. It is also one of the largest urban parks in the world, with a size two-and-a-half times that of the consolidated city and county of San Francisco.