By far the best way to find interesting places which may not be in your guide books, is to speak to the locals when you arrive at a place.

One point of interest which comes to mind is about 20 miles north of Belle Fourche SD, up highway 85, on a side road (old 85), is a small monument in a farmer's field, just off the road, to mark the 'Centre of the Nation'. One of those quirky little attractions you just gotta see. There is nothing at all there, other than the survey marker and the cairn, adorned by Old Glory.

At the visitor centre in Belle Fourche there is a replica, since (they say) most folk do not want to take the extra trip to see the real spot. To me the drive was so worth it.

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Lifey who knows you will find lots of interest