The Knobstone Trail runs 58 miles across the Norman Upland of southern Indiana through Clark, Scott, Washington, and Jackson counties. The terrain is defined by the knobstone — erosion-resistant chert that caps ridges and makes for rocky, uneven footing unlike the flat Midwest stereotype. The trail climbs and descends relentlessly, with no single climb exceeding 400 feet but cumulative elevation gain of 8,000–10,000 feet for the full route. It is, mile for mile, the most demanding trail in Indiana.

Day hikers most commonly access the trail at the Deam Lake State Recreation Area trailhead (northern terminus) or the Spurgeon Hollow trailhead near Brownstown for a 6–8 mile out-and-back along the central ridge. The trail passes through mature second-growth hardwood forest with virtually no facilities and no marked water sources; carry all the water you need. Wildlife is plentiful: white-tailed deer, wild turkey, and occasional coyote sightings are common. The ridge-top views through the trees are best in winter when the leaves are down.

The Knobstone is best hiked in April–May and October–November. Summer is brutally hot and humid; winter can bring ice on the steep knob slopes. There is no fee to hike and no permit required. Dogs are allowed. Camp at designated sites or obtain permission for primitive camping on state forest land.