Perpetual Vigil A soldier assigned to the 3rd U.S. Infantry Regiment, known as “The Old Guard” guards the Tomb of the Unknown Soldier at Arlington National Cemetery in Virginia, Dec. 14, 2020. The site has been guarded continuously since July 2, 1937. SHARE: Download: Full Size (1.83 MB) Tags: army Credit: Army Sgt. Gabriel Silva VIRIN: 201214-A-OA805-005Y.JPG Photo Gallery