The American Discovery Trail is a system of recreational trails and roads that collectively form coast-to-coast hiking and biking trail across the mid-tier of the United States. Horses can also be ridden on most of this trail. The coastal trailheads are the Delmarva Peninsula on the Atlantic Ocean and the northern California coast on the Pacific Ocean. The trail has northern and southern alternates for part of its distance, passing through Chicago and St. Louis respectively. The total length of the trail, including both the north and south routes, is 6,800 miles (10,944 km). The northern route covers 4,834 miles (7,780 km) with the southern route covering 5,057 miles (8,138 km). It is the only non-motorized coast-to-coast trail.