The 2nd pic down is Devil's Tower in Wyoming. I had a snow ball fight there in the middle of the night on one of my many "take off & drive" run's with my USAF buddies. What a blast that was. Good times!!
I also see the Corn Palace in Mitchell, SD and buffalo.....are they in the Black Hills, SD. I thought is was awesome to see those huge things right next to the car on a public road.
Oh and Wall Drug! I love how they advertise for this place as soon as you enter the state.

Did you guys hit up the Badlands?