Location: Located on Alcatraz Island, included in the Golden Gate National Recreation Area, in San Francisco Bay.
Latitude: N 37.8262
Longitude: W 122.4222
Year Constructed: 1909 (station established 1854). Active
Tower Height: 84 feet Focal Plane: 214 feet
Octagonal pyramidal reinforced concrete tower, unpainted. The original 4° Fresnel lens (1902, transferred from the earlier lighthouse) is in storage for future display.
Alcatraz Lighthouse was completed by July of 1853 and was the first lighthouse activated on the West Coast. Light from a fixed, third-order Fresnel lens was first shown from the Alcatraz Lighthouse on June 1, 1854. The lens had been in use for just under fifty years, when in 1902 it was transferred to the Cape Saint Elias Station in Alaska and replaced by a revolving fourth-order Fresnel lens.
Around the time the lighthouse was completed, military fortifications were also placed on the island, the Alcatraz Citadel. In 1909, the Citadel was razed and in its place the present cell house was built. With its 600 cells, the cell house was reportedly the largest reinforced concrete building in the world. Realizing that the new structure would interfere with the operation of the lighthouse, a taller 84-foot, concrete tower was built just south of the original lighthouse. Attached to the base of the tower was a commodious dwelling designed for three keepers and their families.
On June 1, 1970 a fire destroyed the warden's house, the keepers' quarters and other buildings on the island. Today, only the tall cement tower equipped with a modern beacon stands as a reminder of the keepers who served on the island for over a hundred years.
Point Diablo Lighthouse
San Francisco, California
Location: Point Diablo is located about halfway between the northern end of the Golden Gate Bridge and Point Bonita, helping to mark the entrance to San Francisco Bay.
Latitude: N 37.8201
Longitude: W 122.4995
Year Constructed: 1923. Active
Tower Height: N/A Focal Plane: 85 feet
Navigation light mounted atop a square 1-story wood fog signal building. Building painted white.
Point Diablo is located roughly midway between Point Bonita and Lime Point on the northern side of the Golden Gate. The point protrudes some 600 feet into the waters from the Marin Headlands, making the point, according to the Lighthouse Service, "a dangerous menace to vessels entering San Francisco Bay in foggy weather."
In 1923, the Lighthouse Service decided to mark this navigational hazard, and a small white shack with a pitched red roof was placed on the sloping point some eighty feet above the water. The structure housed two lens lanterns and a 12-inch electric siren.
An array of solar panels now powers the modern beacon positioned atop the shack. The light flashes every six seconds, and when necessary the fog signal alerts mariners to the presence of menacing Point Diablo.
Lime Point Lighthouse
San Francisco, California
Location: This lighthouse sits at the foot of the north end of the Golden Gate Bridge
Latitude: N 37.82545
Longitude: W 122.47859
Year Constructed: 1900 (fog signal station established 1883). Inactive
Tower Height: N/A Focal Plane: 15 feet
The 1-story brick fog signal building was converted to a lighthouse in 1900 by mounting a navigation beacon on the wall of the station.
Lime Point is situated on the northern side of the Golden Gate’s narrowest point. From this point, a rocky spur, just twenty feet wide, extends roughly 100 feet into the bay. In 1883, a narrow one-story fog signal building and a two-story keeper’s dwelling were constructed along the spur. The fog signal building was positioned closest to the water, so its two twelve-inch steam whistles, powered by coal-fired boilers, could warn vessels away from the rocky hazard.
Fog posed a very serious danger to vessels, especially near San Francisco, and in the late 1800s, fog signal stations were established at Año Nuevo, Point Montara, Lime Point and Point Knox. A light was added at Año Nuevo in 1890, and a decade later, it was decided that the keepers at the remaining three fog signal stations should also exhibit a light. Accordingly, on November 26, 1900, lens lanterns were lighted at the three stations, and California now had three new lighthouses. The lens lantern at Lime Point was hung on the wall of the fog signal building at a height of just nineteen feet above the water.
Lime Point was automated in July of 1961, and the three-story dwelling and other outbuildings were torn down. All that remains of the station today is the pocked fog signal building, which mostly goes unnoticed by the throngs of tourists that come to admire the impressive art deco bridge.