Washington, D.C. formally the District of Columbia and commonly referred to as Washington, the District, or simply D.C., is the capital of the United States. The architecture of Washington varies greatly. Six of the top 10 buildings in the American Institute of Architects' 2007 ranking of America's Favorite Architecture are located in the District of Columbia, including: the White House; the Washington National Cathedral; the Thomas Jefferson Memorial; the United States Capitol; the Lincoln Memorial; and the Vietnam Veterans Memorial. Washington, is a national center for the arts. The John F. Kennedy Center for the Performing Arts is home to the National Symphony Orchestra, the Washington National Opera, and the Washington Ballet. The city is also a prominent center for national and international media.