Badlands, Gateways, and Ghost Towns - Hardcoverby Jan Cerney (Author) Before the early 1900s, the northern edge of the eroded White River Badlands was virtually impenetrable except for the precarious horseback trails that reached the plain below. The "Badlands Wall" is an escarpment that separates the upper prairie from the lower prairie for 60 miles. In 1907, the Chicago, Milwaukee & St. Paul Railroad pushed west from Chamberlain and reached the lower plains of the Badlands. Small towns sprang up