Shawnee National Forest covers 280,000 acres of southern Illinois and is the main reason visitors come to Carbondale. The forest is unusually wild-looking for the Midwest — dramatic sandstone bluffs, natural arches, cypress swamps, and hardwood ridges give it a character more like the Ozarks or Appalachians than the flat Illinois most people imagine.
The most popular sites are Garden of the Gods (a series of dramatic sandstone formations with views over the forest canopy), the Giant City State Park (prehistoric stone forts built of massive sandstone slabs), and the Cave in Rock (a large cave opening onto the Ohio River). All are within an hour's drive of Carbondale. Rock climbing, rappelling, canoeing, and backpacking are all well-catered for; the forest has over 160 kilometres of hiking trails.