Tomb of the Unknown Soldier-- Part 5: Twenty-One

The Sentinels keep watch 24 hours a day, 365 days a year, in heat, cold, rain -- and even hurricanes.  Three guard shifts work 24-hour shifts, each guarding the Tomb for one hour.

Everything is done in the number 21 because it symbolizes the highest military honor that can be bestowed: the 21-gun salute.

The sentinel walks 21 steps behind the Tomb of the Unknowns, turns, faces east for 21 seconds, turns and faces north for 21 seconds, then takes 21 steps back and repeats the process.

The weapon always remains between the crowd and tomb to signify that the Sentinel stands between the tomb and any possible threat.