Peak to Peak from Clingman's Dome to Waterrock Knob via the MST.
The 46.8-mile-long Segment 1 of the Mountains-to-Sea Trail (MST) begins in Great Smoky Mountains National Park (GSMNP), straddling Tennessee and North Carolina. Heading eastbound, the trail starts at the observation tower on top of Clingmans Dome at the state boundary. After paralleling the road to Clingmans Dome for a few miles, it heads deep into the woods on the longest roadless stretch of the MST—22.8 miles with no road access. Emerging to US 441 at Mingus Mill, the segment continues past the GSMNP's Oconaluftee Visitor Center and Mountain Farm Museum and along the Oconaluftee River, popular for tubing.
From here, the trail continues along the shoulder of the BRP for several miles, with two short trail sections to avoid tunnels (in which walking is prohibited). The BRP is famous for the views from its overlooks, and this segment features several. Turning to gravel roads, the route continues through the Qualla Boundary, home of the Eastern Band of Cherokee Indians, before returning to hiker-only trail for the last 6.4 miles to Waterrock Knob.
(Or you can run the other direction.)