Special Collections has four collections of material for researchers interested in John Wesley Powell and the western U.S.
- a manuscript collection of correspondence and articles written by researchers who have contacted IWU for information on Powell over the years,
- a collection of books by and about Powell and the American West,
- a wide range of material collected by Marcia Thomas during two years of research for the award-winning volume John Wesley Powell: An Annotated Bibliography, and
- a web-based collection of images providing access to the John Wesley Powell Collection of Pueblo Pottery. The physical collection is located on the first floor of the library.