how long has the us guarded the tomb of the unknowns?
One of their most recognized responsibilities is providing sentinels...Tomb Guards, at the Tomb of the Unknown Soldier. Since April 6, 1948 the Tomb of the Unknown Soldier has been guarded 24 hours a day, 365 days a year, regardless of weather. Millions of Americans annually visit the Memorial Amphitheater to watch these dedicated soldiers of a new generation, dutifully pace 21 steps across a black mat on the west face of the Tomb.