A U.S. Marine Corps AAV7A1 assault amphibious vehicle assigned to Alpha Company, 3rd Assault Amphibian Battalion proceeds along a route cleared by Marines assigned to Mobility Assault Company, 1st Combat Engineer Battalion while conducting complex obstacle breaching exercises during Steel Knight 2014 (SK-14) on Camp Pendleton, Calif., Dec. 10, 2013. Steel Knight enables 1st Marine Division to test and refine its command and control capabilities by acting as the headquarters element for a forward-deployed Marine expeditionary force. (U.S. Marine Corps photo by Cpl. Alejandro Pena, 1st Marine Division Combat Camera/Released)