On County Road 318 just east of Fl State 301 near Citra, this is one of those hiking and horseback riding areas that you are prone to drive by daily without thinking to make a stop. In fact, I did just that for close to year.
It's an amazing area for hiking south of Hawthorne and Gainesville and north of Ocala once you do stop. If there is a downside, it's that the trails are maintained by machine tilling up the soil which, in this area, creates a lot of soft, sweet sand to trudge though. But the trails are wide enough to walk along in the grass in these recently tilled area.
Numerous trails greet you, each well-blazed. I made use of red, white, and yellow trails to create two loops (a sort of figure-8) over about seven miles, but there were numerous other connectors and trails to follow. The terrain is flat, it is diverse and includes a very nice pier overlooking a small, unnamed lake or marshland.
Parking is ample, including for your horse trailer, but it's rare to see anyone else there. When you do, the conservation is area is large enough that you won't likely meet them so you have this hike to yourself and your dog, friend, or date.
While the sand is too soft for enjoyable biking in the woodsy trails, a main dirt road will provide the workout you crave, and there are few better places for hiking or horseback riding in the area.