Do: Hike the Lone Tree Loop Trail, but only if you’re willing to get a little muddy. The river crossing weeds out many hikers, so you’ll have most of the trail to yourself (along with the wildlife) should you decide to hike up the pants and make the ford.
See: Buffalo, almost anywhere in the Park. You can hear them from what seems like hundreds of yards away, they stand defiantly in the road, and roam the edges of trails across the South Unit (and almost certainly the North Unit as well).
Drive: The 36-mile Scenic Loop Drive. This spectacular stretch of road affords travelers stunning views of the buttes, wildlife, and in autumn, yellow and orange foliage dotted across the Park.
Stay: Cottonwood Campground offers above-average camping facilities, interesting ranger-led nature talks, and most importantly, a prime central location in the South Unit.
Eat: I can’t recommend any restaurants in the area, as I did not patronize them, but should you find yourself heading east towards Fargo, stop in Bismarck and hunker down at Fried’s Family Restaurant for some delicious breakfast food.