The “Five-Minute Tunnel” will experience about five months of repairs, from January 2 to early May 2017.

The Baker-Barry Tunnel, a main artery into the Marin Headlands, will be entirely closed to all users (motorists, cyclists, and pedestrians) for the duration of the project. This will affect access to destinations such as:

Marin Headlands Visitor Center

Headlands Center for the Arts

Rodeo Lagoon/Rodeo Beach

Fort Cronkhite

Golden Gate Raptor Observatory

Marine Mammal Center

Battery Townsley

Nike Missile Site

Point Bonita

Although these locations still may be accessed via Conzelman Road, that route is expected to see heavy traffic and congestion. In addition, parking at Battery Spencer—as well as pull-outs on Conzelman Road (east of the McCullough Road traffic circle)—will be closed until early May.

Visitors are strongly encouraged to avoid Conzelman during peak times: weekday rush hours from 3 to 7 pm, and weekends (especially after 2 pm). For photographers looking to shoot the Golden Gate Bridge, park officials recommend Fort Baker and Crissy Field as alternatives.

The closure is necessary to complete numerous safety improvements to the historic tunnel. Crews will repair the concrete (leaks have led to the hazardous slick surface in the tunnel), and replace aging water and sewer lines that have been vulnerable to breaks, causing closures over the years.

The project will also install brighter LED lights, improving visibility for cyclists and motorists alike. The tunnel has been the single largest user of energy in Golden Gate National Recreation Area, and the new system will reduce energy consumption by 40 percent.

“Short-term inconvenience will lead to significant long-term gains in safety and sustainability,” said Nathan Hale Sargent, a National Park Service spokesman for Golden Gate. “We thank our community members for their patience and understanding during this important project.”

For more information and the latest updates on the closure (and scheduled reopening), visit http://go.nps.gov/tunnel.