University of Illinois Astronomical Observatory - Credit: Wikimedia Commons
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.University of Illinois Astronomical Observatory , NHL Database, National Historic Landmarks Program. Retrieved April 28, 2007. Read more on Wikipedia
Source: en.wikipedia.org