NORAD 60th Anniversary 5k Tunnel Run
Runners participating in the North American Aerospace Defense Command 60th Anniversary 5k run passed security forces members, assigned to the 721st Mission Support Group, and the blast doors that guard the inside of the Cheyenne Mountain Complex, Colorado, May 10, 2018. The 5k is one of many events held to celebrate NORAD’s 60th year anniversary. (U.S. Air Force photo by Senior Airman Dennis Hoffman)