Lusk Creek Wilderness is a 6,293-acre roadless forest landscape in southern Illinois within Shawnee National Forest near Eddyville, and it is the state's largest wilderness area. It includes the Lusk Creek Canyon National Natural Landmark and is known for hilly terrain, cliffs, and overlooks cut from Carboniferous gray sandstone, often compared to the scenery of nearby Garden of the Gods Wilderness. Much of the land had been pasture before condemnations in the 1930s allowed cleared hillsides to return to forest. Sugar maples and beeches dominate the terraces, while hickory and white oak are common on the slopes. The area was formally protected under the Illinois Wilderness Act in 1990.