U.S. Marines wait for the last Marine to enter Forward Operating Base Shamsher after a patrol in the Sangin district in Afghanistan's Helmand province, Sept. 6, 2012.

The Marines are assigned to Bravo Company, 1st Battalion, 7th Marine Regiment, Regimental Combat Team 6.

U.S. Marine Corps photo by Lance Cpl. Jason Morrison

All the photos of the Marines on patrol in the Sangin district, Afghanistan in the slideshow below

Video about the Marines' efforts in Sangin over a 20 month period