The University of Florida (Gainesville, FL), has a small nuclear reactor on campus. My mom always talked about it when I was young as she worked in the nuclear engineering department. I just checked and it's still active. Apparently it's been online since 1959.

https://news.ufl.edu/2025/10/uf-students-join-elite-ranks/

https://neup.inl.gov/infrastructure/university-research-reac...