Extreme temps, and exposed rock led to Lakota calling this Land Bad. The French said it was Bad Lands to travel through. For us most of it was a nicely paved road with convenient turn outs for photo ops.
We stayed at the Badlands Interior Motel and Campground just outside the park- cheaper and apparntly better than the campground just in the park. Being outside the park gave us a great view of The Wall.
The Wall is the natural, impenetrable rock barrier that extends for miles - impenetrable except for the aforementioned road.