Josephine Sculpture Park, Exit 53 B westbound, 53 A eastbound, Frankfort, about 5 minutes off highway
Free, User Submitted, dawn to dusk
User says: "There's plenty of room to wander, a variety of mowed grass paths -- also it's free and open every day." It looks pretty cool, and there are about two miles of trails. I'm guessing no bikes.
This looks fun: "Bring your own spray paint, paint pens, or permanent markers and make your mark on this sculpture (pictured below) created by JSP 2018 Artist in Residence Peyton Scott Russell."