You walk down into French Canyon and the sandstone closes in. At the bottom, you are walking in the creek, walls close enough that the sky is a slit. The waterfall at the end drops into a bowl you can stand in.
LaSalle, Ottawa, and St. Louis Canyons each do that same pinch, a few ridges apart. A sandstone slot, then a fall into a bowl, then the trail is done.
Starved Rock State Park sits on a bluff above the Illinois River. The canyons cut back into the sandstone from that rim, and the rim looks down on the lock and dam and the wide water under the bluff. Spring snowmelt and rain, from April into May, run French, LaSalle, Ottawa, and St. Louis the hardest. You hear the fall before the last turn, then the canyon ends in wet rock and a white drop.
September and October put color on the rims. The campground inside the park books out then, so lock the site first if fall is the season you want. In winter, bald eagles work the open water below the lock and dam, and you watch from the bluff. Down in the canyons, the waterfalls freeze into ice columns, and French, LaSalle, Ottawa, and St. Louis become walks through standing ice.
The Starved Rock campground is the first night. Book the site through the Illinois state park system before you book the van, because fall is the weekend that fails if you reverse that order. I-80 west toward Utica is the road in. The Starved Rock park page has gates at 8:30 a.m. to 10 p.m. daily as of September 2026.
Matthiessen State Park is the next set of slots, narrow box-canyon dells crossed by footbridges. The Dells lot fills and closes to new arrivals by about 11 a.m. on May through October weekends as of September 2026. Buffalo Rock State Park is a bluff overlook of that same river, with the Effigy Tumuli earthworks in the grass. There is no campground on the bluff.
Route 66 through downtown Joliet
Joliet is the first city on Route 66 once you leave Chicago. The old alignment runs through downtown, and that street is the other half of this trip. Get out for the Rialto Square Theatre and walk the ornate lobby, historic Union Station, and the Blues Brothers statues on the roof of Rich and Creamy. Downtown is a day stop, and the van sleeps at the Starved Rock campground.
The Old Joliet Prison is limestone cell-block wings and a guard tower. Those are the walls from the opening of The Blues Brothers, and the buildings still stand on Collins Street.
The Illinois and Michigan Canal still leaves town at Rockdale, which borders Joliet. The maintained 61.5-mile towpath runs west toward LaSalle.
Kankakee River State Park
The Kankakee River runs over a limestone bed with rapids in the channel, and canoe put-ins sit along the bank. The park follows that river for 11 miles and holds more than 200 campsites, booked through the same state system. When Starved Rock is full, this is the closer overnight.
A van is enough sleeping space for this river overnight. If you need more bunks than that, Illinois RV rentals are the step up.
Fourth of July weekend already fills Illinois state parks. NASCAR Cup racing at Chicagoland Speedway lands on that same holiday, so the race and the campgrounds pull on the same vans and the same sites.
Lake Michigan and the Indiana Dunes sit on the Chicago campervan page. For the rest of Illinois, start with the Illinois campervan page.