Flags In Soldiers assigned to the 3rd U.S. Infantry Regiment, known as “The Old Guard,” place American flags at headstones in Arlington National Cemetery, Arlington, Va., May 21, 2020. The tradition, known as “Flags In,” is held annually prior to Memorial Day to honor the nation’s fallen veterans. SHARE IMAGE: Download Image: Full Size (4.64 MB) Tags: Observances, Army Photo By: Elizabeth Fraser, Army VIRIN: 200521-A-IW468-752.JPG Photo Gallery