The AIB’s four main halls radiate in the shape of a Greek cross from the central Rotunda; they contain 17 total individual exhibition areas, providing over 7,432.24 square meters (80,000 square feet) of floor space. The halls have their own separate roofs, and rise in height as they lead through a large open arch to the Rotunda in the center of the building. They were designed to be high ceilinged, vast open areas, not only for aesthetic effect but also to allow for the greatest diffusion of light and for maximum flexibility of exhibits.
Construction of the National Museum was undertaken primarily to relieve pressure on the increasingly overcrowded Smithsonian Institution, and to provide much needed additional space to house artifacts. As a result, when the Museum first opened in 1881, a large amount of unsorted materials, still in their crates – from skeletons to airplanes – occupied most of the exhibition halls. By the end of 1883, after two years of effort, only three of the museum’s 17 hall areas were still in use for storage of unsorted materials.
The Halls continued to exhibit collections until the building closed to the public in 2004, Seen here is the South Hall in 1904 full of exhibits that eventually went to the new National Museum in 1911 (renamed the National Museum on Natural History). Also seen is the North Hall which exhibited the Star-spangled Banner for many years. Seen in the 1950s being cleaned, it was moved in 1964 and can be seen in the National Museum of American History.