Langley Air Force Base Airmen participate in the Security Forces 9/11 Ruck March to Remember near Amherst, Va., Aug. 25, 2011. They marched in remembrance of the 10th anniversary of 9/11 and the defenders who have fallen by enemy hands since the start of Operation Enduring Freedom. (U.S. Air Force photo by Tech. Sgt. Barry Loo/Released)