Postcard, "Library of Congress, Washington, D.C.," circa 1916

United States lawmakers established the Library of Congress in 1800. For nearly 100 years, the growing library occupied limited space in the U.S. Capitol. Congress eventually authorized the construction of a permanent building in 1886, and the structure opened in 1897. Since its founding, the Library of Congress has become one of the world's largest repositories of recorded knowledge.