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Level: Intermediate
Length: 4 mi (6.4 km)
Surface: Singletrack
Configuration: Out & Back
Elevation: +2,076/ -1,175 ft
Total: 6 riders

Mountain Biking CDT: Tunnel Lake

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#353 of 1,353 mountain bike trails in Colorado
#3,416 in the world

Running 4.4 miles one-way, this chunk of the CDT gets very high into the alpine, way above treeline, after climbing through a beautiful pine forest. The southern end of this trail connects to the Alpine Tunnel trail, forming a commonly-ridden loop with the Alpine Tunnel Trail, Tincup Pass Road, and Hancock road.

First added by Greg Heil on Aug 22, 2014. Last updated Apr 28, 2020. → add an update
Before you go
  • Drinking water: unknown
  • Lift service: unknown
  • Night riding: yes
  • Pump track: unknown
  • Restrooms: unknown
  • Fat bike grooming: unknown
  • E-bikes allowed: unknown
  • Fee required: unknown
This trail information is user-generated. Help improve this information by suggesting a correction.
Getting there
Tincup Pass
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CDT: Tunnel Lake Trail map

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Trail conditions

(on Jan 31, 2023)
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Rider questions

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  • John Fisch

    Tough stretch of singletrack connecting the roads at the either side of the Alpine Tunnel Loop. The climb from the tunnel is heinous, but delivers the rider to a lengthy traverse above treeline with classic Colorado high country scenery. The plunge down the other side is wicked good fun. Some may grouse about the tight switchbacks interrupting flow, but I just made them part of the flow. It's one of those descents in deep, dark woods you just want to go on forever.

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  • Greg Heil   ✓ supporter

    This section of singletrack is the true jewel along the Alpine Tunnel loop. All singletrack, with awesome switchbacks through the trees and mind-blowing above alpine traversing, this trail is a fantastic high elevation mountain biking experience.

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