South Dakota is great. The Black Hills are awesome and Mt. Rushmore is something every American should see.
This Canadian has seen Mt. Rushmore...loved the Black Hills, though the camping choices were limited and not really camping. I mean my choices were to pay $50+ per night for a campsite that had no vegetation on the ground but did have a pool and waterslide and Flintstones theme park...or $10 per night for a spot that had grass, but no firepit/bbq or separation between the sites. My idea of camping includes a place to have a fire and an unpaved, ungraveled place to pitch my tent.