If you really need a trail, Buffalo Gap has one. It's called the Prairie Bike Trail and you'll find it between the town of Wall and Badlands National Park. Take Interstate 90 and get off at Exit 116, then head just a little west. Prairie Trail is nestled underneath some badland escarpments, and crosses a missile site—which some might find interesting— as well as some cattle fences.

But why limit yourself? Except for the Indian Creek Roadless Area, bikes are welcome everywhere in Buffalo Gap. The Grasslands are criss-crossed with four-wheel drive roads and double-track trails that make for good biking, especially if you want to test your navigational skills. Disorientation is a real issue here: land tends to be level and landmarks subtle, so an odometer on your bike to double-check distances is very useful.

The Ward Dam Road is another recommended bike route. You'll find it 25 miles southeast of Rapid City near Farmingdale. Take SD 44, head east just over 1 mile to CR C-459 and go south 3. 5miles to the junction with FS 7056. You can park here and start your ride. You'll begin by riding west on FS 7056 toward the Ward Dam. The clearest track goes through a fence, about 4 miles from the start, heads to another fence, then drops down to the small reservoir and wildlife preserve at the damsite. From the south side of the reservoir, a less distinct track begins the climb to the south toward a butte that has a small stand of cedar trees on the side. You can keep that destination in sight as you follow tracks south for over 1 mile, keeping right, eventually making a rocky ascent onto that hill at another fence line. There will be great views of the Rapid Creek valley ot the north and east to the Railroad Buttes. There are other possible places to explore from here.

Wherever you go in the grasslands, watch out for tire-puncturing native cactus—and be sure you have a repair kit with you.