WASHINGTON (Army News Service, May 27, 2011) -- The cemetery here is fluttering with patriotism after members of the Old Guard placed flags in front of more than 260,000 gravesites in advance of Memorial Day.Each year, 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.The tradition, known as "flags in," has been conducted annually since The Old Guard was designated as the Army's official ceremonial unit in 1948. Every available Soldier in the 3rd U.S. Infantry participates, placing small American flags one foot in front and centered before each grave marker.At the cemetery, flags are placed in front of gravestones and 7,300 niches at the columbarium. Additionally, about 13,500 flags are placed at the Soldier's and Airmen's Cemetery in the District of Columbia.On Monday, May 30, the U.S. Army Military District of Washington will conduct an Armed Forces Full Honor Wreath-Laying Ceremony 11 a.m. at the Tomb of the Unknowns in Arlington National Cemetery.That ceremony will be followed by an observance program hosted by the Department of Defense in Arlington's Memorial Amphitheater. A prelude by the U.S. Marine Band will begin in the amphitheater at 10:30 a.m.Both the wreath-laying ceremony and the observance program are free and open to the general public. Attendees are encouraged to be at the Tomb of the Unknowns or seated in the amphitheater by 9:30 a.m.