Four Nike Ajax missiles stand ready for launch at an Army air defense battery sited on hillside terrain overlooking a nearby valley. Fielded beginning in 1954, the Nike Ajax was the U.S. Army's first operational guided surface-to-air missile, deployed at fixed batteries encircling major American cities and strategic coastal areas. Many such sites, particularly along the West Coast, were operated jointly by active-duty Army and Army National Guard air defense units as part of the nation's Cold War-era continental defense network. Project: 218663