Out of all the nature hotspots around UF, the Ichetucknee River is one of the best. Forty-five minutes north of Gainesville, the Ichetucknee rises from a series of first magnitude springs, and flows south into the Santa Fe River. You can swim in the two sources springs at the North Entrance, Ichetucknee and Blue (pictured), or you can rent a tube and float down from the South. I always describe the river to friends as the lazy river, an eternally 72 degree stream of clear water filled with turtles, fish, and, at this time of year, manatees.
The best time for wildlife viewing is winter and early spring, while the water is still used as a warm shelter and before the crowds set in. If you go now, however, you might want to bring a wetsuit, as it can get pretty chilly.
A tram runs from the South Entrance Memorial Day through Labor Day, saving you a short hike up the river.
Without further ado, I present to you: The Itchetucknee River: