The Smithsonian Institution in Washington is unique in the world of museums. For most Americans it is their favourite, one they are sure to visit when they come to the federal capital, and revisit whenever possible. Its curious Gothic castle building on the Mall, such a contrast to the opulent classicism of the Capitol and the National Museum of Art, seems oddly un-American at first, as though it had been designed by Prince Albert, with forceful suggestions by Queen Victoria. Inside, however, it is very American indeed, housing a wonderfully rich collection of Americana, some of it rare and valuable, such as literary and musical manuscripts and historic documents, some of it bric-a-brac which has led to the nickname ‘America’s attic’. Items include Lincoln’s top hat, the aircraft in which Lindbergh first flew the Atlantic solo (The Spirit of St Louis), and the first US space capsule. Its shop is a must for tourists because it sells first-class replicas of everything remarkable in America and such elaborate reconstructions as complete recordings of 1920s musicals. Its Space Center is the best thing of its kind in the world. However, it is much more than that. With its annexes and affiliated museums, libraries and research branches, it is by far the largest museum-and-knowledge complex on earth, used by countless scholars in every conceivable discipline, though with a distinct bias towards science and technology.