I used to live in OK, up north of Tulsa near the Kansas border, and there are still parts of the old Route 66 in place between Tulsa and OK City. My experience is that, to get the best out of the mid-west, you need to get off the interstates and major state highways - they are very, very dull - and find the roads that take you the back way into the heart of the smaller communities, and have enough time to linger and bump into the local folk, even if its just to stock up on root beer. Don't rush it or try to cover crazy distances*. Stay in small towns or in state parks. The experience is unlike anywhere else on earth. Of course you'll want to visit the big sites too, but I'd suggest looking for a tour that offers more than just a chance to check things off the bucket list. *A friend and I once did a weekend trip to in Santa Fe, NM - 1500 miles round trip, leaving Friday night, back by Sunday night. It was the kind of trip you have to do once, but never want to do again. I clearly remember running over an armadillo on the last mile before getting home - <> it went under the wheels of mile half-ton Ford Mercury. The next morning on the way home, I looked out for its remains, but there wasn't anything there - it had just got up from the road and wandered off home. Of course, given how exhausted I was, I could have just imagined the whole thing...