U.S. Marines Combat Instructors with the School of

U.S. Marines Combat Instructors with the School of Infantry-East begin their five-hour night navigation course; an event in the Combat Instructor Stakes on Sept. 10, 2015. The Combat Instructor Stakes is a grueling 32-hour competition that pits two man, Combat Instructor teams against each other competing in physical, tactical and knowledge based events while carrying a combat load and moving over 55 Kilometers on foot. (U.S. Marine Corps Photo by SOI-E Combat Camera, Cpl. Andrew Kuppers/Released)