On the windswept face of the Marin Headlands overlooking Rodeo Beach, Brad Higley is busy patching a piece of Battery Mendell, an old Army fortress that is more than 100 years old.
Work on the decaying, cracked mass of concrete may seem futile, or even bordering on lunacy. But keeping the old fortresses intact is important to the Golden Gate National Recreation Area.
"Part of our mandate is to protect and preserve these types of cultural resources that we have," said Alex Picavet, spokeswoman for the GGNRA. "We also want to arrest the decay where it's possible."
With about 15 million people a year visiting the recreation area, the curious are drawn to the old military sites. They also have to be maintained for safety.
"There are people climbing all over these things on the weekends and they are at some incredibly scenic locations," said Fairfax resident John Martini, a Bay Area historian who has studied and written about the old military batteries. "They are all very historic."
Beginning with Fort Point, which sits underneath the Golden Gate Bridge, military minds sought to protect the entry point into San Francisco Bay. Work on Fort Point started in 1853.
The hills in Marin high above the Golden Gate provided the perfect vantage point to lob armaments at an attacking force. By the early part of the 20th century the U.S. Army built Battery Mendell and four other batteries at Fort Barry in the Marin Headlands. Mendell -- which was completed in 1906 -- was outfitted with a pair of 12-inch guns on a "disappearing carriage," according to the park service. When the guns were ready to fire, they would pop up into position, fire a single shot, and then recoil down and out of sight for reloading, Martini said.
Both the guns and soldiers were hidden from the enemy behind a concrete parapet.
During World War II, Mendell was upgraded with anti-aircraft guns and became part of the Harbor Defenses of San Francisco charged with defending the area from enemy attack. Because aircraft were not part of warfare when it was built, Mendell had to be outfitted with camouflaged nets over its top to keep it hidden, Martini said.
The invaders never came and what was left was a mosaic of structures that dot the Marin's landscape. Over the years they fell into disrepair, but today they are not being allowed to crumble away.
"The beams were half gone, half deteriorated because of the corrosion," said Higley, pointing to a part of Battery Mendell, as he worked on the structure last week.
Co-owner of Auburn-based DBI Construction, Higley has been working on shoring up batteries for the last two decades.
"It's heavily visited and this being a national park they want to maintain it for public safety," he said. "It's either that or close it off and they don't want to close it off. There are way too many visitors."
There are challenges to the work, which is tested by the environment and conforming with history.
"The methods and procedures are specialized for the marine environment here," he said. "And we try to maintain the historic profiles with the repairs in terms of color and texture so that ideally you can't see the repairs."
As Higley stood on a ladder, parging a beam overhead as fog set in over the area, he spoke of the work he does on the old structures.
"People come by and thank the park service for maintaining this for their enjoyment," he said with a smile. "People come here from all over the world to look, or they grew up here and they played here in their youth. They are happy to see it's maintained. I get that comment often."
Contact Mark Prado via email at firstname.lastname@example.org