Appalachian Trail is a 142.18-mile out-and-back foot trail in Great Smoky Mountains National Park, Tennessee. It climbs 8,219 ft to a high point of 6,519 ft. Difficulty: very strenuous, from the NPS hiking-rating formula.

Hike to Mount Le Conte on the Appalachian Trail and Boulevard Trail
Length 16.2 miles (26.1 km) roundtrip Parking & Trailhead Please consider a shuttle or park at Newfound Gap Overlook on US 441/Newfound Gap Road.
Read the official NPS description
The Park Service lists a shorter hike along this trail: Hike to Mount Le Conte on the Appalachian Trail and Boulevard Trail, 16.2 mi round trip. The whole mapped trail is 142.18 mi.
Open Appalachian Trail on Trailbound's interactive map to see the full route, the elevation profile, today's forecast and any park alerts for Great Smoky Mountains. Great Smoky Mountains has permits or reservations for some areas: see the Great Smoky Mountains page for what's needed.