U.S. Soldiers with the 3rd U.S. Infantry Regiment (The Old Guard), place American flags in front of fallen veterans' gravestones during "flags in," at Arlington National Cemetery, Va., May 23, 2013. Each year for the past 40 years, members of the 3rd U.S. Infantry (The Old Guard) has honored America's fallen heroes by placing American flags before the gravestones and niches of Service members buried at both Arlington National Cemetery and the U.S. Soldier's and Airmen's Home National Cemetery just prior to Memorial Day weekend. This tradition, known as "flags in," has been conducted annually since The Old Guard was designated as the Army's official ceremonial unit in 1948. (U.S. Army photo by Sgt. Jose Torres Jr.)

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