(Encyclopedia) Yerba Buena Island, 300 acres (121 hectares), W Calif., in San Francisco Bay. It is the midpoint of the San Francisco?Oakland Bay Bridge, which crosses the island through a tunnel.? (Encyclopedia) Goat Island. 1 Former name of Yerba Buena Island, San Fransisco Bay, Calif. 2 Island, W N.Y., in the Niagara River, dividing Niagara Falls into the American and the Canadian falls. (Encyclopedia) San Francisco?Oakland Bay Bridge, double-decked structure, W Calif.; built 1933?36 and (eastern section replacement) 2002?13. It has a total length of 8.25 mi (13.2 km). From San? (Encyclopedia) San Francisco Bay, 50 mi (80 km) long and from 3 to 13 mi (4.8?21 km) wide, W Calif.; entered through the Golden Gate, a strait between two peninsulas. The bay is as deep as 100 ft (30? (Encyclopedia) Alcatraz ?lk?tr?z? [Sp. lcatraces=pelicans], rocky island in San Francisco Bay, W Calif, about one mile (1.61 km) north of San Francisco. Alcatraz was first sighted by the Spanish in?