Even if two feet of snow hits the Washington, D.C. area or temperatures rise above 100 degrees, sentinels from the 3rd U.S. Infantry Regiment (The Old Guard) stay outside no matter what. Their job is to guard the Tomb of the Unknown Soldier 24 hours a day, every day of the year, in any weather, in full dress uniform with an M-14 rifle. They march for 21 paces in front of the tomb, face north to stand at attention for 21 seconds, then march 21 paces back. The Tomb of the Unknown Soldier is a memorial to the dead of World War I, World War II, the Korean War and the Vietnam War. Inscribed on it are the words, 'Here rests in honored glory an American soldier known but to God.'