The Marin Headlands make up the area just north of the Golden Gate Bridge in San Francisco. There is a road that turns off Hwy 101 and leads into the Marin Headlands from where you can get fantastic views of the Golden Gate Bridge. In fact, many of the shots you have ever seen of the bridge were most likely taken from there.
What a lot of people do not know is that there are many other photo opportunities to be found when you continue down that road (most people shoot the bridge, then turn around and go back). Below is one of those opportunities that present themselves. This is the Point Bonita Lighthouse, built on this rocky outcrop in the Golden Gate National Recreation Area.
The lighthouse is still in active use today and is maintained by the US Coast Guard and is open to visitors (although the bridge is being replaced at time of writing this making the lighthouse inaccessible until spring 2012).