The Splitsonian Institution is a humorous analog of the Smithsonian Institution, which is spread out over several buildings - the Castle, the Museum of American History (known as the Museum of National History at the time this show aired), the Museum of Natural History, and the Air and Space Museum, among others. The Splitsonian haphazardly lumps together bits and pieces from all of these and more into one building, whose exterior resembles the Castle.