The University of Illinois Astronomical Observatory, located at 901 S. Mathews Avenue in Urbana, Illinois, on the campus of the University of Illinois Urbana–Champaign, was built in 1896, and was designed by Charles A. Gunn. It was listed on the National Register of Historic Places on November 6, 1986, and on December 20, 1989, was designated a National Historic Landmark. Though none of the astronomical instruments are being used for professional research today, the observatory still contains a …