U.S. Air Force transport aircraft sit on the snow-covered ramp at Thule Air Base, Greenland, during the early 1950s. Built beginning in 1951 above the Arctic Circle, Thule became a vital Cold War outpost supporting strategic bomber staging, ballistic missile early-warning radar, and polar resupply missions, all conducted in some of the harshest operating conditions faced by American servicemen. Project: 218295