Washington Monument | Washington DC

The Washington Monument is an obelisk on the National Mall in Washington, D.C., built to commemorate George Washington, once commander-in-chief of the Continental Army and the first President of the United States.

Located almost due east of the Reflecting Pool and the Lincoln Memorial, the monument, made of marble, granite, and bluestone gneiss, is both the world's tallest predominately stone structure and the world's tallest obelisk, standing 169.046 meters tall. It was the tallest structure in the world from 1884 to 1889, when it was overtaken by the Paris' Eiffel Tower.

For ten hours in December 1982, the Washington Monument and eight tourists were held hostage by a nuclear arms protester, Norman Mayer, claiming to have explosives in a van he drove to the monument's base. U.S. Park Police shot and killed Mayer. The monument was undamaged in the incident, and it was discovered later that Mayer did not have explosives. After this incident, the surrounding grounds were modified in places to restrict the possible unauthorized approach of motor vehicles.

At 1:51 p.m. on August 23, 2011, a magnitude 5.8 earthquake struck 90 miles southwest of Washington, D.C. Visitors inside the Washington Monument's observation deck were thrown about by the force of the shaking; falling mortar and pieces of stone caused minor injuries, though all the people inside exited safely. A National Park Service spokesperson reported that inspectors discovered a crack near the top of the structure, and announced that the monument would be closed indefinitely.

Sketch of the proposed Washington Monument by architect Robert Mills.