State Park / State Forest · Illinois campground guide
The numbers
Fee range
$20–$35/night
Season open
April through October
RV size limit
Up to 50 ft
Reservation window
6 months ahead via IL ReserveAmerica
The insider read
10 connected lakes — Illinois's largest interconnected waterway. Boat rentals at the marina; weekend traffic on the chain is heavy summer. Class A loop has the longest sites for big rigs.
Original analysis from PickRV — synthesised from public sources you can verify, pulling the operational details competitor guides typically skip.
Verify at dnr.illinois.govOn site
Book it right
PickRV doesn't handle campground bookings — reserve direct through the official channel so policies and cancellations flow through one record.
Opens reserveamerica.com
Every fact above is sourced from the managing agency's canonical page. Cross-check fee, season, and size limit before you depend on them.
Match the campground's size limit and hookup level to a vehicle category, then plan the rest of the trip.
Keep exploring
Near Grafton
StateInsider tip · Illinois River + Mississippi confluence — bald eagles winter (Dec-Feb) on the bluffs. The lodge serves Sunday family-style fried chicken — only state-park restaurant of its caliber in Illinois.
Near Benton
COEInsider tip · Largest USACE camp in southern Illinois. Rend Lake bass-tournament traffic March-May; book the family-quiet weekends June-July. USACE Senior Pass halves the fee — apply at gate not online.
Near Brimfield
StateInsider tip · Historic 1839 Episcopal college site — restored chapel + period buildings open weekends. Equestrian camp area separate from RV/tent loop. Mountain bike trail system 22 miles.
Near Marshall
StateInsider tip · Memorial to the Lincoln family's 1830 Indiana-to-Illinois route. The 146-acre lake bans gas motors — paddleboard or kayak only. Sites in 'A' loop have the lake views.
Your next step
Chain O' Lakes State Park Campground takes rigs up to 50 ft, so what you arrive in decides whether the loop works at all. If you don't own one, the same trip runs on a motorhome rented in Illinois.
Nothing in Illinois is bookable today. Dated requests are what we take to owners, so give us the window you actually want — you get one email the day a rig covers it, and nothing else.
Nearby & related
Sourced costs, campground directories, and the places worth a detour — the next layer of Illinois trip planning.
Before you go
Illinois rules
Verified 2026-05-10
