A 3.5-m reflector originally operated by Wisconsin, Indiana, and Yale Universities, plus the National Optical Astronomy Observatory (hence WIYN). In 2014 Yale was replaced by the University of Missouri. It is situated at Kitt Peak National Observatory and began operation in 1994. It is designed for wide-field spectroscopic observations. In 2001 the WIYN consortium took over operation of the NOAO 0.9-m reflector, originally opened on Kitt Peak in 1960.

http://www.noao.edu/wiyn/ Official telescope website.