Sergeant Osmel Delgado, the 2nd section leader, and Sgt. Matthew R. Sanville, the 3rd section leader, with 3rd Platoon, Charlie Company, 2nd Assault Amphibian Battalion, look over which part of the map they want their Marines to use to create a terrain model at Fort A.P. Hill, Va., June 2, 2013. Participating in land navigation and building a terrain model began because of down time in a training environment.