WASHINGTON (Army News Service, May 24, 2013) -- A sea of tiny American flags flutters gently in the breeze now at Arlington National Cemetery. The flags were placed at gravesites, May 23, in tribute to the service and sacrifice of the nation's fallen service members who rest there.In advance of Memorial Day, Soldiers from the 3d U.S. Infantry Regiment (The Old Guard) carefully placed the flags by hand, one by one, in front of each of the gravestones at the cemetery."I think every Soldier you will talk to, especially the Old Guard alumni, [say] that for them, Flags In is one of the most meaningful things that Old Guard Soldiers get to take a part in," said Maj. John Miller, spokesman for the Old Guard. "It's just overwhelming that you can go out and be amongst all these warriors that have gone before you and you can honor their legacy by just a single token of putting a flag at their gravesite and giving them a hand salute."The Flags In event is an old tradition at the cemetery, Miller said."Flags In is a tradition that the Old Guard has carried on now for over 40 years -- though nobody has an exact date," he said.The tradition actually dates back much further even -- there was a break in the tradition for a while. But it was revived by the Old Guard after World War II."It dates back to the Grand Army of the Republic in 1868, whenever they began the holiday inside Arlington by honoring all the Union Soldiers that had fallen during the Civil War," Miller said. "They began placing flags on tombstones for Memorial Day."About 1,200 Old Guard Soldiers participated in the event this year, and about 220,000 graves received a flag, as did memorial markers and rows of urns at the cemetery's columbarium. Miller said the Soldiers were able to accomplish the task in about four hours -- beginning after the last full-honors funeral ended at the cemetery. That means, for the graves alone, a Soldier placed a flag every 80 seconds.The major said that Soldiers do a row of gravestones by putting their toe against the center of the stone, and then placing the flag at their heel. In that way, every row has the flags placed equidistant from the stone, giving a uniform appearance. Uniformity and perfection is something that the Old Guard prides itself on, Miller said."The Old Guard Soldiers are the last thing that a family sees as they bury their loved one from the Army," he said. "And that's what we try to give every service member's family. Their final vision of the Army is one of perfection and professionalism, and that is how we try to honor the fallen service members in the cemetery every year as well."While each grave marker at the cemetery received a flag, so too did the service members interred at the Tomb of the Unknowns. There, members of the public stood at quiet attention as Tomb Sentinels placed flags at the graves of each of the four unknown service members within the tomb. Additionally, about 13,500 flags were placed at the Soldier's and Airmen's Cemetery in Washington, D.C.