I would say, most likely, Montana and Wyoming. Also the Dakotas west of the Missouri River. The entire area is sparsely populated and even though the USA's western frontier was pretty much 'closed up' by about 1890, a lot of those old cultural vestiges remain.Hallo from Denmark
My son talks about, that he likes to experience real cowboy western indian culture, like in Back to the future 3. And maybe also a modern large city still with western culture.
Which state to visit?