Machine gun nest

One of the most exciting elements of the wide variety of coastal fortifications that can be found in the San Francisco area is the recent discovery of previously unknown World War II machine gun nests, some of which are within feet of roads through the city's Presidio. Here, the machine guns--probably a .50 caliber weapon--were mounted on the pillar that can be seen here, and were most likely placed where they could cover important roads--like this one--or crucial beaches.

The National Park Service is trying to weigh the balance between allowing the public to visit these sites, and the potential danger of damage to delicate areas of having thousands of people walking through.