Library of Congress, National library in Capitol Hill, Washington, D.C., United States.

The institution occupies three connected buildings on Capitol Hill and holds more than 164 million items including manuscripts, maps, photographs, and recordings. It functions as the national library of the United States and serves Congress as well as researchers from around the world.

President John Adams established the institution in 1800, initially housed within the Capitol building itself. The move to the current main building occurred in 1897 when the collection outgrew its original location.

The library's Hispanic Reading Room, created in 1939, is named for the Hispanic Society of America. Its collections span more than 470 languages, and the oldest item is a stone tablet from 2040 BC. The Library of Congress also appoints the United States Poet Laureate.

Free guided tours run from Tuesday through Saturday between 10 AM and 5 PM, with extended hours until 7 PM on Thursdays. The exhibition galleries are open to everyone, while reading rooms require registration for serious research purposes.

The collection includes one of three perfect copies of the Gutenberg Bible on vellum, displayed in a dedicated case within the Thomas Jefferson Building. The building also houses personal items from famous Americans, including the contents of Abraham Lincoln's pockets from the night of his assassination.