This ICBM silo, near Willsboro, has been taken over by artists. Known as Atlas Silo 556-4, it is one of a dozen intercontinental ballistic missile silos in the region, built in the early 1960s. They were controlled out of the air force base at Plattsburgh, and were the only ICBM silos ever built east of the Mississippi. Six were constructed inside Adirondack Park, making it, at one time, the best defended park in the nation. All of the silos were decommissioned in 1965, and most are now in private hands.