Participants of Marine Corps Community Service's "World Famous Mud Run," sponsored by U.S. Marine Corps Forces, Special Operations Command, take off from the starting line June 4, 2011. The 10k race is part of MCCS's Hard Corps Race Series. (Official U.S. Marine Corps photo courtesy of Monroe photography/Released) - Participants of Marine Corps Community Service's "World Famous Mud Run," sponsored by U.S. Marine Corps Forces, Special Operations Command, take off from the starting line June 4, 2011. The 10k race is part of MCCS's Hard Corps Race Series. (Official U.S. Marine Corps photo courtesy of Monroe photography/Released)