Editing Arlington National Cemetery (section)

===Tomb of the Unknown Soldier===
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{{Main|Tomb of the Unknown Soldier (Arlington National Cemetery)}}

The [[Tomb of the Unknown Soldier (Arlington)|Tomb of the Unknown Soldier]] stands on top of a hill overlooking Washington, D.C. One of the more well-attended sites at the cemetery, the tomb is made from Yule marble quarried in Colorado. It consists of seven pieces, with a total weight of 79 [[short ton]]s (72 [[metric ton]]s). The tomb was completed and opened to the public 9 April 1932, at a cost of $48,000.

Other unknown servicemen were later placed in crypts there, and it also became known as the Tomb of the Unknowns, though it has never been officially named. The soldiers entombed there are:
* Unknown Soldier of [[World War I]], entombed 11 November 1921; President [[Warren G. Harding]] presided
* Unknown Soldier of [[World War II]], interred 30 May 1958; President [[Dwight D. Eisenhower]] presided
* Unknown Soldier of the [[Korean War]], also interred 30 May 1958; President Dwight Eisenhower presided again, Vice President [[Richard Nixon]] acted as next of kin
* Unknown Soldier of the [[Vietnam War]], interred 28 May 1984; President [[Ronald Reagan]] presided. The remains of the Vietnam Unknown were disinterred, under the authority of President [[Bill Clinton]], on 14 May 1998, and were identified as those of Air Force first Lt. [[Michael Blassie|Michael J. Blassie]], whose family had them reinterred near their home in [[St. Louis, Missouri]]. It has been determined that the crypt at the Tomb of the Unknowns that contained the remains of the Vietnam Unknown will remain empty.

The Tomb of the Unknown Soldier has been perpetually guarded since 2 July 1937, by the U.S. Army. The [[3rd United States Infantry Regiment (TOG)|3rd U.S. Infantry Regiment]] ("The Old Guard") began guarding the Tomb on 6 April 1948. There is a meticulous routine that the guard follows when watching over the graves.<ref>{{cite web|archive-url=https://web.archive.org/web/20110925062923/http://www.arlingtoncemetery.mil/VisitorInformation/ChangingofTheGuard.aspx |archive-date=September 25, 2011 |url=http://www.arlingtoncemetery.mil/VisitorInformation/ChangingofTheGuard.aspx |title=The Changing of the Guard |location=Arlington County, Virginia |publisher=Arlington National Cemetery |access-date=January 21, 2012 |url-status=dead }}</ref> The Tomb Guard:
# Marches 21 steps southward down the black mat behind the Tomb
# Turns left, facing east for 21 seconds
# Turns left, facing north for 21 seconds
# Takes 21 steps down the mat
# Repeats the routine until the soldier is relieved of duty at the [[guard mounting|changing of the guard]]

After each turn, the Guard executes a sharp "shoulder-arms" movement to place the weapon on the shoulder closest to the visitors to signify that the Guard stands between the Tomb and any possible threat.

Twenty-one was chosen because it symbolizes the highest military honor that can be bestowed{{snd}}the [[21-gun salute#United States|21-gun salute]].

At each turn, the guard makes precise movements followed by a loud click of the heels as the soldier snaps them together. The guard is changed every half-hour during daylight in the summer, and every hour during daylight in the winter and every two hours at night (when the cemetery is closed to the public), regardless of weather conditions.

[[File:Arlington Amphitheater 1922 U.S. stamp.1.jpg|thumb|right|Arlington Amphitheater 1922 issue]]
A commemorative stamp was issued on 11 November 1922, the first anniversary of the first entombment picturing the Amphitheater. It encompasses the original Tomb of the Unknown Soldier. The remains of an unidentified American soldier from World War I were entombed on Armistice Day, 11 November 1921, later covered in 1931 by a more elaborate marble sarcophagus.<ref>Juell, Rod. "50-cent Arlington Amphitheater", Arago: people, postage & the post, National Postal Museum online, viewed March 12, 2014.</ref>