There are no bike rental places in the Badlands, so you have to bring your own or rent bicycles in Rapid City and haul them to Badlands National Park. Bikes are not allowed on the hiking trails, or in the backcountry wilderness areas, but they are allowed on the paved and gravel roads in the park. A brochure on loop trips on combined park and county roads is available at the visitors center.
During peak season in the summer, bikers should be cautious on the Badlands Loop Road, since it is not a wide road and there can be a lot of traffic. It can be an exhilarating ride, however, and from the Pinnacles Overlook to the visitors center it is 22 miles of mostly downhill riding.
Slightly more off the beaten path is the Sage Creek Rim Road. This 22-mile gravel road skirts the northern edge of the wilderness area, runs past the Roberts Prairie Dog Town, and passes though the lowest and oldest layers of the Badlands formations.
For the adventurous, a less-traveled and equally beautiful road open to bicyclists can be found in the South Unit of the park. Sheep Mountain Road is located about four miles south of the town of Scenic off of County Road 589/BIA 27. It is a seven-mile-long, dead-end dirt road with spectacular views of the South Unit of the park and of the Black Hills, 70 miles to the west. It is a moderately strenuous ride with a total elevation gain of about 400 feet. The most strenuous part of the ride is a 250-foot climb at the end of the road to the top of Sheep Mountain table. To shorten the ride, it is possible to drive in with a vehicle, pull off the road, and park. The road can be impassable when wet. There are no services here, so bring plenty of water.
© Laural A. Bidwell from Moon Mount Rushmore & the Black Hills, 1st Edition