Mill Creek Wilderness is a protected backcountry area in central Oregon's Ochoco National Forest, established in 1984 and encompassing 17,400 acres. The largest and most heavily used of the forest's three wilderness areas, it is known for rugged terrain including steep canyons, barren ridges, high meadows, stone pinnacles, and the volcanic Twin Pillars. Bingham Prairie provides a strikingly flat contrast of open meadow and lodgepole pine forest. Drained mainly by Mill Creek and Marks Creek, the area is also known for thundereggs, mature ponderosa pine, and wildlife such as elk, black bear, mountain lion, and trout, despite fire and beetle damage.