Near Wall, the 64,250-acre Sage Creek Unit of Badlands National Park is home to one of the best treks. Park at the Sage Creek primitive campground and strike out for the Wall, an assortment of steep, crumbling ridges about seven miles away. There are no set trails--bison paths are your surest guides. Camp anywhere amidst the spires and pinnacles, and carry in all the water youll need.
To reach the hiking trailhead from Rapid City, take US 90 east 56 miles to Wall, go south on SR 240 to the Pinnacles park entrance, and then head west on Sage Creek Rim Road to the Sage Creek Campground.
Overall, Badlands National Park is the 1st most popular hiking trail of all 10 hikes in South Dakota.