Some of the state universities in Pennsylvania are suprisingly isolated. Most obvious is Mansfield University. I'm not sure where the hell you would go to fly out--I think there's a commuter airport 40 miles south in Williamsport, but US may have pulled out of there. Clarion University has a commuter airport about 40 minutes away (in two different directions), but they were without service for an extended period after the US Pittsburgh contraction. (I think CO is serving them now into CLE.) Some of the other ones are a distance away from airports like Harrisburg.
Elmira-Corning airport (in New York) is about a half-hour away from Mansfield, and there's competition there, with flights to Detroit, Philadelphia, and Orlando(!).
Among large universities, it's worth mentioning Brigham Young University in Provo, Utah--more than 30,000 students, but the nearest airport with scheduled service is (I think) Salt Lake International, one hour away, even assuming no traffic.