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Parks and recreation

Several of San Francisco's parks and nearly all of its beaches form part of the regional Golden Gate National Recreation Area, one of the most visited units of the National Park system in the United States with over 13 million visitors a year. Among the GGNRA's attractions within the city are Ocean Beach, which runs along the Pacific Ocean shoreline and is frequented by a vibrant surfing community, and Baker Beach, which is located in a cove west of the Golden Gate Bridge, as well as the California Academy of Sciences, a research institute and natural history museum.

The Presidio of San Francisco is the former 18th century Spanish military base, which today is one of the city's largest parks and home to numerous museums and institutions. Also within the Presidio is Crissy Field, a former airfield that was restored to its natural salt marsh ecosystem. The GGNRA also administers Fort Funston, Lands End, Fort Mason, and Alcatraz. The National Park Service separately administers the San Francisco Maritime National Historical Park – a fleet of historic ships and waterfront property around Aquatic Park.

There are more than 220 parks maintained by the San Francisco Recreation & Parks Department. The largest and best-known city park is Golden Gate Park, which stretches from the center of the city west to the Pacific Ocean. Once covered in native grasses and sand dunes, the park was conceived in the 1860s and was created by the extensive planting of thousands of non-native trees and plants. The large park is rich with cultural and natural attractions such as the Conservatory of Flowers, Japanese Tea Garden and San Francisco Botanical Garden.

Lake Merced is a fresh-water lake surrounded by parkland and near the San Francisco Zoo, a city-owned park that houses more than 250 animal species, many of which are endangered. The only park managed by the California State Park system located principally in San Francisco, Candlestick Point was the state's first urban recreation area.

Most of San Francisco's islands are protected as parkland or nature reserves. Alcatraz Island, operated by the National Park Service, is open to the public. The Farallon Islands are protected wildlife refuges. The Seal Rocks are protected as part of Golden Gate National Recreation Area. Red Rock Island is the only privately owned island in San Francisco Bay, but is uninhabited. Yerba Buena Island is largely utilized by the military.

San Francisco is the first city in the U.S. to have a park within a 10-Minute Walk of every resident. It also ranks fifth in the U.S. for park access and quality in the 2018 ParkScore ranking of the top 100 park systems across the United States, according to the nonprofit Trust for Public Land.