Arlington Cemetery was established at the former estate of Robert E. Lee during the Civil War and is currently administered by the Department of the Army and the National Park Service. Just outside of Washington, DC, it overlooks Memorial Bridge and the Lincoln Memorial.
The Cemetery currently covers 624 acres and is divided into 70 sections. There are more than 400,000 interments, with an average of 25 new interments conducted each day. For this reason the flags are flown at half mast.
The Tomb of the Unknowns is located at Arlington Cemetery, at the entrance to the Amphitheater, and is guarded by the 3rd US Infantry Regiment (also known as the Old Guard.) During visitor hours, the guard is changed every 30 minutes, and every 2 hours when the Cemetery is closed.
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