The Bighorn National Forest begins almost at Sheridan's western edge and extends across more than a million acres of mountain terrain. US Route 14 and 14A both climb over the range, offering spectacular switchback roads to alpine elevations with wide views of the Wyoming basin beyond. The routes are passable most years from late May to October.
The Cloud Peak Wilderness at the centre of the forest is the serious backcountry option — multi-day hiking with granite peaks, alpine lakes, and solitude in quantities that are increasingly rare in the American West. For day visitors, the forest has fishing streams, campgrounds, cross-country skiing in winter, and the Antelope Butte Ski Area for downhill. Sibley Lake is a good picnic and swimming destination in summer.