A little south is the babcock/webb recreataion area. Babcock/Webb - Recreation
The entry to it is just off i-75 at trucker grade so it easy on easy off i-75, I know because i drive past it all the time and use the bathroom there now and again on trips to and from miami
I have not drove back to the camping area but if you look at it on google maps.............sat view. Get off on trucker grade and go east.........as you pan east you see that first larger lake on the south with a road on the west side of it? follow that road south just a bit and you can clearly see the camping area and what looks to be mid sized rvs in it......................................... I just looked closer street view works in the camping area so you can take a close look.
Look at the web page close and the closed days involving hunting season and non hunting season.
I been meaning to go spend a weekend there for a while but i got busy then it got really hot!
I do think you have to purchase a daily use permit that I think is 6 dollars per vehicle so maybe it does not count as free but damn close.