Free Camping in Kentucky
While the Bluegrass State isn't exactly carpeted in free RV camping, there are certainly camping areas where you can find a place to call home "rent-free," and they're spread across the state evenly enough no matter which corner of KY you're interested in exploring.
Free RV Camping in Daniel Boone National Forest
When it comes to the great state of Kentucky, free camping is most abundant in Daniel Boone National Forest. One of the most natural settings you'll find in that forest is Beaver Creek Wilderness, and while motorized vehicles are prohibited within the wilderness area itself, free dispersed camping is permitted along Swain Ridge Road. Note that camping on public lands comes with more challenges than your typical RV camping experience. Don't expect much in the way of amenities, including bathrooms or trash service, and know that you'll be expected to pack out everything you brought with you if you want to take advantage of this type of wild camping.
Otherwise, be prepared for a serene experience where camping is on a first-come, first-served basis. You'll likely have few neighbors, though expect the forest service to occasionally do a drive-by or check in on you.
That said, there are even a few free campgrounds–with vault toilets, a picnic table, and fire rings at designated sites–throughout Daniel Boone National Forest. These camping locations are all situated about an hour and a half south of Lexington, KY, and include the S-Tree and Turkey Foot Campgrounds. You'll find more dispersed camping, without toilets, East of Lexington at Paragon Dispersed Camping Area near Cave Run Lake.
Free RV Camping Opportunities via Kentucky Department of Fish & Wildlife Resources
Primarily located along the southern stretches of the state, wildlife management areas provide more options to find free RV camping sites. Campers can find spots along Lake Mauzy and near boat ramps outside of Redbird, KY, along the Cumberland River, and near Kevil, KY, on the Mississippi River.
Note that these areas are not always specifically designated for camping alone. They are popular with fishermen and hunters, so check ahead with the fish and wildlife service as to what hunting season you may be looking at before choosing one of these places as your ultimate camping destination.
The Army Corps of Engineers also manages a free campground at Wilson Creek Recreation Area on Green River Lake.
Free RV Camping in Parking Lots
Looking for a quick overnighter as you traverse the Bluegrass State? Though more akin to "RV parking" than camping, you'll find many free to stay parking lots across Kentucky at places like Walmart and Cabela's. Keep in mind these are privately owned businesses that are nice enough to allow RVers a place to stay for the night, so a modicum of restraint should be used in keeping your rig neat and not treating the place like a tailgate party.
A few rest areas along Interstate highways offer overnight parking as well. Always check for signage indicating whether there is a stay limit, or have a friendly conversation with any local law enforcement likely to patrol the lots before setting up camp. Like with camping in parking lots, it's best to refrain from putting out your awning, setting up the camp chairs, and making a spectacle of yourself, as a rest area is for exactly that–a free place to get some rest, not your own personal recreation area.