A U.S. Marine enrolled in Officer Candidate School low-crawls under a barbed wire obstacle on the Montford Point Challenge obstacle course at Marine Corps Base Quantico, Va, Dec. 8, 2012.
The Montford Point Challenge was designed in 2011 to give officer candidates a taste of the hardships of the first African-Americans allowed to enlist in the Marine Corps. (DoD photo by Sgt. Christopher A. Green, U.S. Marine Corps/Released). Original public domain image from Flickr