Library of Congress: The Library of Congress is the national library (National libraries) of the United States. Founded in 1800, the Library of Congress was originally housed in part of the Capitol building. In 1897, the Library got its own building (now known as the Jefferson Building). The Guinness Book of World Records currently lists the Library of Congress as the "World's Largest Library". This apparently is based on the shelf space the collection occupies.
The Library of Congress states that its collection fills about 530 miles (850 km) of shelves. It holds about 130 million items with 29 million books. It is estimated that the print holdings of the Library of Congress would, if digitized and stored as plain text, constitute 17 to 20 terabytes of information.