Run for the Fallen event
Senior Airman Shannon Banks, 60th Civil Engineer Squadron firefighter, rings the firefighter's bell before the Run for the Fallen event on Sept. 10, 2016 at Travis Air Force Base, Calif. The ringing of the bell symbolizes the end of a firefigher's duty, and was rung to honor the 343 firefighters who lost their lives on Sept. 11, 2001. (U.S. Air Force photo by Senior Airman Shelby R. Horn/Released)