We have been to all of those places many times. Recommending places to stay is tricky because some people want all the amenities and some prefer boondocking. As a first timer, you will have different things to see because theyíre new. Start by making a list of things to do. For example, in Yellowstone, you have all of the thermal features and geysers. The wildlife isnít always in those areas, so you will want to go to the Lamar and Hayden Valleys at sunrise/sunset to see wildlife. I would recommend staying in West Yellowstone to see thermal features and then move to Cooke City and Boondock there to see the wildlife. In the Blackhills there are a number of nice Passport America parks that provide good access to the Wind Cave, Custer State Park (especially wildlife loop), Mount Rushmore, and Deadwood areas. Personally, I would plan 3 days in the south and three days in the north. Plan a stop at Devilís Tower and Little Bighorn between the Blackhills and Yellowstone. Enjoy the trip.
Ron and Terrie Ames with Sirius - MOC #1920
2015 Montana 3160 Legacy Package
2019 Ram 3500 Laramie Longhorn
4x4, SRW, SB, Mega Cab, Pullrite 2600 Hitch