there's so much to do it's not even funny... it just depends on which route you're taking through the state...
check out their tourism website... hot springs has an awesome mammoth dig site museum, you can see where they filmed "dances w/ wolves", there's mount rushmore... into wyoming there's devils tower... i believe the 1880's train is still taking tours from hill city to keystone... wind cave is pretty cool... custer state park, the badlands, you can spend a week in the western half of the state alone... the needles scenic byway has some spectacular scenery... there's almost as much to do there as there is in wyoming... it's just in a much more confined space... lol...
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