The Pentagon is the headquarters building of the United States Department of Defense. As a symbol of the U.S. military, the phrase The Pentagon is also often used as a metonym for the Department of Defense and its leadership.

Where is the Pentagon actually located?

Pentagon, large five-sided building in Arlington county, Virginia, near Washington, D.C., that serves as the headquarters of the U.S. Department of Defense, including all three military services—Army, Navy, and Air Force.

Why is the Pentagon in Virginia?

Congress passed a law in 1945 to clarify that the National Airport was located within Virginia. ... The Pentagon was built inland from the high-water mark, so it is located within Virginia. The dredge spoils used to create Columbia Island are within the District of Columbia.