Fort Point had three different lighthouses , the first beginning in 1852 . The third lighthouse, which still stands today, was placed on a metal tower capping one of the fort's circular stairways. At 106 feet above sea level, the light could be seen by sailors along the entire horizon. A larger fourth-order Fresnel lens soon replaced the smaller original lens. The last keeper locked the door to the lighthouse on September 1, 1934, when the rising Golden Gate Bridge blocked the light and muffled the sound of the fog signal.