Point Bonita Lighthouse

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Point Bonita Lighthouse
Point Bonita Lighthouse, January 2013.jpg
Point Bonita Lighthouse is located in California
Point Bonita Lighthouse
Location San Francisco Bay, California
Coordinates 37°48′56″N 122°31′47″W / 37.815569°N 122.529604°W / 37.815569; -122.529604Coordinates: 37°48′56″N 122°31′47″W / 37.815569°N 122.529604°W / 37.815569; -122.529604
Year first constructed 1855
Year first lit 1877
Automated 1980
Foundation Masonry
Construction Brick and Cement
Tower shape Polygonal on building
Markings / pattern white
Height 33 ft (10 m), 124 ft (38 m) above sea level
Original lens Second order Fresnel lens
Current lens Second order Fresnel lens
Range 18 nm
Characteristic Occulting white once every 4s. Emergency light of reduced intensity when main light is extinguished. HORN: 2 blasts ev 30s (2s bl-2s si-2s bl-24s si).
Admiralty number G4052
ARLHS number USA-618
USCG number 6-0370

Point Bonita Lighthouse is a lighthouse located at Point Bonita at the San Francisco Bay entrance in the Marin Headlands near Sausalito, California. Point Bonita was the last manned lighthouse on the California coast.

History[edit]

The original Point Bonita Lighthouse, a 56-foot (17 m) brick tower, was located too high. Unlike the East Coast of the United States, the West Coast has dense high fog, which leaves lower elevations clear. The original light was 306 feet (93 m) above sea level so the second order Fresnel lens was often cloaked in fog and could not be seen from the sea. In 1877, the lighthouse was moved to its current location at 124 feet (38 m) above sea level. The United States Coast Guard currently maintains the light and fog signal. It is accessible to the public during limited hours (12:30 PM–3:30 PM) on Saturdays, Sundays, and Mondays. Up until 1940 the lighthouse could be reached without a bridge, but erosion caused a trail leading to the lighthouse to crumble into the sea. A wooden walkway was installed, but when that became treacherous the suspension bridge was built in 1954.

As of January 6, 2010, the suspension bridge to the light house was closed to public access. According to the Federal Highway Administration, the bridge, which was 56 years old, started to rust. It underwent repairs in 1979 and again in 1991, but the metal components were not able to stand up to the sea spray. The new span reopened April 13, 2012. The new bridge construction cost a bit over $1 million. It is made of tropical hardwood with steel suspension cables and attachments.[1]

Historical Information from USCG web site:

  • Point Bonita Light Station had the first fog signal on the West Coast. It was an Army surplus 24-pounder siege gun.
  • This light is the only one in America that can be reached only by crossing a suspension bridge.
  • In 1877 the lighthouse was moved to its current location because the original location was often too obscured by fog for the light to be visible from the bay. This location required the builders to overcome many challenges, including the need for a hand carved, 118-foot (36 m) long hard rock tunnel.[2]

More than 300 boats ran aground near the Golden Gate during the Gold Rush years. One shipwreck, the SS City of Rio de Janeiro, is just a few hundred feet offshore from the light.

Image gallery[edit]

References[edit]

  1. ^ http://www.marinij.com/marinnews/ci_17028695
  2. ^ "Historic Light Station Information and Photography: California". United States Coast Guard Historian's Office. Retrieved 2008-08-19. 

External links[edit]