SF-88 is a former Nike Missile launch site at Fort Barry, in the Marin Headlands to the north of San Francisco, California, U.S. Opened in 1954, the site was intended to protect the population and military installations of the San Francisco Bay Area during the Cold War, specifically from attack by Soviet bomber aircraft. The site was originally armed with Nike Ajax missiles, and modifications were made to the site in 1958 to allow it to also be armed with Nike Hercules missiles. In 1974, SF-88 was closed, but was not demolished. It is now part of the Golden Gate National Recreation Area and is open to visitors. Normal visiting days are Wednesday-Friday, but a special tour with veterans of the base is available the first Saturday of each month. Restoration work to the site is done on remaining Saturdays by volunteers.