The largest library in existence: The Library of Congress. This is the world's largest library, with nearly 110 million items in almost every language and format stored on 532 miles of bookshelves. Its collections constitute the world's most comprehensive record of human creativity and knowledge. Established: April 24, 1800; 218 years ago.
Now the question is: Can anyone enter the Library of Congress? Yes, anyone age 16 and older may use the collections but you need to have a reader card to enter.