Steam foghorn of the East Brother Island Light Station, California.

Prise de son réalisée le 8 mars 2013 par Frank Schulenburg

East Brother Island Lighthouse is a lighthouse located on East Brother Island near the tip of Point San Pablo in Richmond, California. It marks the entrance to San Pablo Bay from San Francisco Bay.
Source :
 East Brother Island Light From Wikipedia in English
 East Brother Island Light From Wikipedia in German

More links :
 East Brother Light Station
 "Historic Light Station Information and Photography : California". United States Coast Guard Historian’s Office.
 East Brother, CA at LighthouseFriends.com
 East Brother Light Station at www.us-lighthouses.com