Pine Lake Park, in western San Francisco and contiguous with Stern Grove, is an elongated valley with steep, forested slopes. Pine Lake is one of the few remaining natural lakes in San Francisco, and is fed by the same aquifer as Lake Merced. The willow, tule, and other wetland plants that ring the lake provide habitat for a variety for resident and migratory bird species. A trail encircles the lake, providing opportunities for viewing birds, and connects to the larger trail network that winds through Stern Grove, including a segment of the Bay Area Ridge Trail.
Pine Lake is an important stop for migratory birds on the Pacific Flyway. More than 250 species of birds can be seen throughout San Francisco during the year, most of which migrate from as far as South America to the Arctic and back. Many of these migrating birds stop only briefly at Pine Lake to feed and rest as they continue their journey to the north or south; others mate, build nests, and nurture a new generation of young birds in San Francisco before returning to their wintering grounds elsewhere.
In 1847, the Greene family moved from Maine to San Francisco for the excellent grazing and farming land, and purchased a large property of which Stern Grove and Pine Lake were only a small portion. In 1887 the family was forced by lawsuit to give up most of the land and keep only the portion that today makes up Pine Lake and Stern Grove. In 1892, George Greene, Jr., built the Trocadero Inn in what is now Stern Grove. It was a Victorian-style roadhouse that operated for more than 20 years, closing when Prohibition was enacted. Pine Lake was then known as Laguna Puerca, or Pig Lake. The Greenes planted the eucalyptus trees that surround the lake.
In 1931, Rosalie Stern, widow of civic leader Sigmund Stern, was looking for land to purchase and donate to the city as a park in honor of her husband. Her friend, Golden Gate Park Superintendent John McLaren, recommended the Greenes’ property at 19th Avenue and Sloat Boulevard. Sigmund Stern Grove opened to the public on June 4, 1932. A San Francisco newspaper reporter wrote, “Thousands of San Franciscans do not even suspect the existence of the lovely redwood and eucalyptus grove that once was part of the old Trocadero ranch. It is way over by Sloat Boulevard, a beautiful amphitheater of hillside, trees, and greensward.”
Over the following five years, the city purchased land west of the original grove, including Pine Lake, enlarging Sigmund Stern Grove. The grove has hosted free summer music concerts every year since 1938.