The Pentagon The Pentagon The Pentagon, in Arlington County, Virginia, across the Potomac River from Washington, D.C., is the headquarters of the United States Department of Defense. As a symbol of the U.S. military, the phrase "The Pentagon" is often used as a metonym for the Department of Defense and its leadership. The building was designed by American architect George Bergstrom and built by contractor John McShain. Ground was broken on September 11, 1941, and the building was dedicated on January 15, 1943. General Brehon Somervell provided the major motivating power behind the project; Colonel Leslie Groves was responsible for overseeing the
Arlington County, Virginia Arlington include: The Doors frontman Jim Morrison; Former vice president Al Gore; Confederate general Robert E. Lee; U.S. Army general George S. Patton, Jr.; astronaut John Glenn; actors Warren Beatty, Sandra Bullock, and Shirley MacLaine; journalist Katie Couric; musicians Roberta Flack and Zac Hanson; physician and social activist Patch Adams; and scientist Grace Hopper. Arlington County, Virginia Arlington County is a county in the Commonwealth of Virginia, often referred to simply as Arlington or Arlington, Virginia. In 2016, the county's population was estimated at 230,050, making it the sixth-largest county in Virginia, or the fourth-largest city if it were incorporated