I'm planning our summer road trip from Chicago to Yellowstone. Cody, WY is our first stop and then 3 nights at Yellowstone. We have already been to SD and thoroughly enjoyed the sites of The Badlands, Black Hills, Mount Rushmore, 1880s Town, Wall Drug, Custer National Park. It is such a beautiful drive through Minnesota and SD. I'm investigating going through Iowa and Nebraska to Cheyenne up to Casper and then to Cody. Suggestions? I've never been to Nebraska nor spent time in Iowa, what fun sites are there to see?