The Knobstone Trail is the longest hiking trail in Indiana. Its southern terminus is about 15 miles (24 km) north of Louisville, Kentucky in the Deam Lake State Recreation Area. It currently ends at Delaney Creek Park near Salem, Indiana. However, there are plans to eventually extend the trail another 80 miles (129 km) north to Martinsville, Indiana. Most of the trail lies within Clark State Forest. As it lies along the Knobstone Escarpment, it is a difficult hike, which is why many use the Knobstone Trail to prepare for hiking the Appalachian Trail.

The trail was first established in 1980, and was only 32 miles (51 km) long. It now runs 58 miles (93 km), mostly through public forest.

Hiking the trail in its entirety results in approximately 20,000 feet (6,100 m) of elevation change between the gains and losses. The trail passes through 3 counties and is surrounded by approximately 40,000 acres (160 km²) of Indiana State Forest. The rugged trail consists of steep climbs and descents throughout its duration. It is maintained to backcountry standards. There are no designated camp sites; rather hikers must camp at least 1-mile (1.6 km) from roads and trailheads.

After a tornado on March 2, 2012, destroyed 4.5 miles of the trail, sections of the trail were closed. The damaged areas were reopened in early 2014.^[1]

Following are waypoints on the trail: