I WISH ILLINOIS HAD THESE KINDS OF PLACES NEARBY INSTEAD OF CORN AND ALL. But yeah, that's a really cool place you found there.
Illinois has these kind of places, I live north of Chicago, and there's a small river (Des Plaines) in the middle of a small forest 2 miles from where I live, it's on the border between Cook County and Lake County, almost next to Lake-Cook Road.
I live in one of those counties. I need to drive there one day. Thank you for informing me of this <3 (also the corn was just a joke if you're wondering)
There's a suburb called Northbrook (where I live), there's a road called Dundee road near Lake-Cook Road, Follow Dundee until you pass on an overpass over I-294, ahead, there is a small forest, and to the left, there's a sign that leads to this picnic area next to the Des Plaines.