The trailhead for this route cannot be reached from the main road through Theodore Roosevelt National Park. To get there from Medora, go west on I-94 then take exit 23. Go north along Forest Service Road 730 and follow the signs for the Petrified Forest. You'll pass a private road sign, but you have permission to continue. Continue on this road until you reach Road 730-2. Turn right then take the first left. A high-clearance vehicle is recommended as the road can have large ruts and potholes.
The majority of this trail is across flat prairie grassland. There's a 175-foot ascent in the first half mile of the trail. Shortly after completing this ascent, you'll see a trail marker at the junction for the north and south trails. There's a 300-foot descent followed immediately by a 300-foot ascent just before meeting the Maah Daah Hey trail. The trail ends with a descent down to the Little Missouri River. You can turn the trail into a 10 mile loop by turning south on the Petrified Forest Loop Trail portion of the Maah Daah Hey then returning via the South Petrified Forest Trail. The trail is well traveled at least up to where it meets the Maah Daah Hey so following it isn't difficult if any of the trail markers have been broken by wildlife. The trail can be slick if it's rained recently. There is almost no shade and no water source, so come prepared.
For those just wishing to view the petrified wood, this trail is about a 3 mile round trip and is family friendly. The most difficult portion will be the initial ascent in the first half mile. There is also a shorter descent to enter the valley where the petrified wood is located.