Standing at 1st Street and East Capitol Street, Southeast of Washington DC, with zip code 20540, the Library of Congress is America?s national library and the biggest library in the world. This historical institution serves as a research body for the Congress. Being one of the most important landmark in Washington DC, the Library consist of three colossal buildings with over a hundred million of materials such as books, maps and manuscript in their countless bookshelves as well as recordings and photographs. Remarkable short films are also played in the first-floor at the visitor area. Highlight of the library is the magnificent Main Reading Room featuring great architectural structure and impressive ceilings.

The Library of Congress has free admission and opens from Monday to Saturday. You can also check http://www.loc.gov/ for more information.