Definitely the Badlands, Custer St. Park. Make sure you take something to feed the donkeys if they are out. They often stop traffic and beg food from the vehicles. We were the cool kids on the block when they found out we had marshmallows. Deadwood was fun to see in the evening after it cooled down. Definitely Spearfish Canyon, several waterfalls. There is a little cafe at the entrance to the canyon at Cheyenne Crossing that the best Indian tacos ever. We stayed at the cabins behind the cafe and ate there several times.
2015 Rockwood 8315 BSS
2015 Silverado 2500HD 6.0
Ginger & Sammie (our 4 legged kids)
US Navy veteran