The Backbone & Iron Mountain Pass (TN-133)
The northern wing of The Snake motorcycle network, connecting Shady Valley to Damascus ('Trail Town USA') across Iron Mountain along Beaverdam Creek. The route carves through The Backbone Rock Recreation Area, featuring 'The Shortest Railroad Tunnel in the World' drilled through a razor-thin rock cliff directly over the highway. The pavement features rhythmic, banked river sweepers tightly enclosed by rock overhangs and rhododendron thickets, with virtually zero runoff room on the creek side.
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The beating heart and tactical checkpoint of 'The Snake' (US-421: 489 curves across 3 mountain ranges in 33 miles). Nestled in an idyllic high mountain bowl, the store is a weekend gathering spectacle of sport tourers, adventure riders, and cruisers resting after surviving the steep Holston Mountain switchbacks.
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Frequently Asked Questions
How many curves and miles is The Backbone & Iron Mountain Pass (TN-133)? ▼
The Backbone & Iron Mountain Pass (TN-133) spans 15 miles and packs approximately 120 curves (8.0 curves per mile) with an elevation delta of 1,920 ft - 3,200 ft and technical rating 8.0/10.
Where are the start and end coordinates? ▼
The route starts at Shady Valley, TN (Latitude 36.5204, Longitude -81.9298) and finishes at Damascus / Whitetop Mountain, VA (Latitude 36.6337, Longitude -81.7832).
How can I download the GPX file for GPS navigation? ▼
Click the "Download Free GPX" button on this guide. The standard XML file is 100% free and ready to load into Garmin zūmo, BMW Motorrad Connected, Rever, Scenic, or Google Maps.