This 4,200-acre panorama of San Diego at play fills with families and friends most weekends, especially in summer. Thousands of parking spaces disappear quickly and cyclists, skaters, joggers, and strollers stream along scenic trails. Volleyball nets, bocce ball courts, and other toys pop up all over the 90 acres of developed public parks as watercraft zoom about in the bay. Early explorers who termed this area False Bay would surely be astonished. The park  opened to the public in 1949, after the Army Corps of Engineers dug channels, dredged tidelands, and shaped the terrain into beaches, coves, and sloping lawns. The park includes a few businesses, Sea World, hotels, sportfishing operations, and sports centers.