The Main Interior Building, also known as the Stewart Lee Udall Department of the Interior Building, located in Washington, D.C., is the headquarters of the United States Department of the Interior. Located in the Foggy Bottom neighborhood, it is bounded by 19th Street NW on the west, 18th Street NW on the east, E Street NW on the north, C Street NW on the south, and Virginia Avenue on the southwest. Although the building takes up the entire block, the address is "1849 C Street, NW" to commemorate the founding of the Department of Interior in 1849. To the east is DAR Constitution Hall, the headquarters of the Daughters of the American Revolution, as well as the World Resources Institute and the American Red Cross National Headquarters. To the west is the Office of Personnel Management head