United States, Tennessee
489 curves in 12 miles over Iron Mountain, a proper southern Appalachian sprint.
Length
19 km
In miles
11.8 mi
Driving time
36 min
Atlas rating
8.9 / 10
The run
Mountain City to Shady Valley, following the US 421. Drive it in either direction, though the views usually favour the climb.
Season
Popular with bikes at weekends
Checked by the Drivers Atlas desk
Scored and written by the Drivers Atlas editorial desk, drawing on driven routes across the UK and Europe, mapping data and member road reports. Every road in the library carries a driving and scenery score set by the same method. How we score roads.
Last reviewed 7 April 2026
Nearby
125 km away
Blue Ridge Parkway
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213 km away
Tail of the Dragon, US129
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Cherohala Skyway
Wide, fast and empty, the grown up alternative to the Tail of the Dragon next door.
380 km away
Skyline Drive
Seventy five overlooks along the Shenandoah ridge, the northern half of the Blue Ridge run.
648 km away
Natchez Trace Parkway
A 715 km parkway with no junctions, no lorries and no billboards, just trees and quiet.
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Tunnel of Trees, M119
A single lane ribbon of tarmac through hardwood forest above Lake Michigan.
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