Washington, DC

ZIP code 20551 is home to the U.S. Department of State headquarters in Washington, D.C. This zip code encompasses the Harry S. Truman Building, where crucial diplomatic decisions are made, and the Dean Acheson Auditorium, which hosts notable events and conferences. Additionally, the area is near iconic landmarks like the White House, the National Mall, and the Lincoln Memorial, making it a hub of political and historical significance.