Free Camping in Illinois
Despite holding the nickname of the Prairie State, Illinois is more likely to conjure up images of the big city as opposed to wide-open spaces. Similarly, free camping is hard to come by–but not impossible to find. The bulk of free RV camping locations to be had in the state will come in the form of private business parking lots, but those are not your only options.
Free Camping in National Forests of Illinois
While primitive tent camping and even car camping opportunities are relatively abundant in the Shawnee National Forest, free campgrounds suitable for RVs are limited. Turkey Bayou, along the Big Muddy River, provides free camping in the campground itself and potential dispersed camping along nearby forest roads. These are your best bet at finding any type of solitude when it comes to free RV camping areas across Illinois. However, as the nearby river's name indicates, doing so is seasonal and getting stuck in the mud is a real hazard.
Always scout ahead before driving down dirt roads, and plan ahead in general. If this is your first time boondocking, you'll want to become familiar with the etiquette and best practices of such an endeavor.
Free Casino Camping in Illinois
If you're the gambling type, Harrah's Metropolis Casino offers free overnight stays in their parking lot. As is typical with casino camping, don't expect much in the way of amenities at your spot–it's simply a free place to stay and at your own risk, more or less.
Still, if playing the slots is your thing, this is a place to find free overnight RV parking.
Free Camping in Private Business Parking Lots
As is true in most of the United States, certain businesses are happy to allow RVers looking for free camping in Illinois to spend a night or two in their parking lots. These include Walmarts, Cracker Barrels across the state, and even a Bass Pro Shop near Peoria.
While you don't necessarily have to check in with the business owners in these locations, it never hurts, and especially if you don't see other RVs doing the same, doing so can help you avoid a knock on the door after nightfall. They do, of course, presume you'll shop their wares, and it is a nice way to say thank you for the spot. It also should go without saying that you are guests of the business and should limit your impact: don't put out your awning and camping chairs. Be discreet and polite so that places like these will continue to offer the same hospitality up for years to come.
More Free Camping in Illinois
Finally, rest stops along the freeway at times allow overnight stays. One specific example in Illinois providing just such a camping experience is near Rend Lake.