Five current and former U.S. Airmen scale a 20,310-foot climb up Denali, the highest mountain peak in North America, Denali National Park and Preserve, Alaska, June 19, 2021. The United States Air Force 50 Summits Challenge is a project focused on helping U.S. Airmen fly the USAF flag from the highest point in all 50 states. The challenge also aims to promote the well-being of Airmen through physical, mental, social and spiritual means. (U.S. Air Force photo by Lt. Col. Robert Marshall)