Hello, we are planning a road trip from northeast Kansas, to South Dakota. We are wanting to cover as many of the top attractions as possible. We will be staying in Rapid City for 3 nights and then we will spend 1 night in Sioux Falls. Please could advise as to which places are a "must-see" and help provide some insight into what places and attractions are the most significant. What are some sights or places that are the key points to visit when travelling to South Dakota?