Ocean Beach runs along the Pacific Ocean shoreline, but is not suitable for swimming because the waters off the coast are perennially cold and form deadly rip currents. Baker Beach is located in a cove just inside the Golden Gate and adjacent to the Presidio, a former military base. Crissy Field, within the Presidio, has been restored to its natural salt marsh ecosystem. All of these together, plus other sites such as Alcatraz and Fort Funston, form part of the Golden Gate National Recreation Area, a regional collection of beaches, parks, and historic sites administered by the National Park Service. The NPS separately administers the San Francisco Maritime National Historical Park—a fleet of historic ships and waterfront property around Aquatic Park.

There are more than 200 parks maintained by the San Francisco Recreation and 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 which houses more than 250 animal species, many of which are designated as 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.