Boulder, CO: Devils Thumb Lake
Leave your car at home: To explore Continental Divide country, you only need a bus ticket and your bike.
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-Mapped by Andrew Matranga

Trail Facts
- Distance: 16.4
Waypoints
DTL001
Location: 39.9533348, -105.526268
From Nederland High School, pedal W on CO 130 through old town of Eldora. Road turns to gravel
DTL002
Location: 39.9519501, -105.5959702
L @ Y to Hessie trailhead (eventually becomes 4WD road)
DTL003
Location: 39.9540329, -105.5997467
Pass shacks of Hessie, an old silver-mining town. 4WD road ends @ bridge over creek. Stash and lock bike, then begin hiking on Devils Thumb Trail, passing waterfalls
DTL004
Location: 39.9555664, -105.6128159
L @ Y, staying on Devils Thumb Trail
DTL005
Location: 39.9545326, -105.6165314
L @ Y onto Lost Lake Trail. Climb 200 ft. under an umbrella of lodgepoles
DTL006
Location: 39.9508247, -105.616806
Lost Lake: Pick a campsite (permits required) along the wooded shoreline. The next day, backtrack to WPT 5 and turn L (bearing W)
DTL007
Location: 39.954216, -105.6196671
Cross South Fork Middle Boulder Creek and continue straight on Devils Thumb Trail
DTL008
Location: 39.9627495, -105.6325531
Swing L @ Y; hillside pockets of aspens. Grind out next 1,000 ft.
DTL009
Location: 39.9746323, -105.651619
L @ T; keep climbing
DTL010
Location: 39.9753342, -105.6613312
Pass W shores of Jasper Lake (10,814 ft.). Roam along a stream lined with grasses and colorful wildflowers. Stunted, bonsai-like pines and firs @ treeline
DTL011
Location: 39.973587, -105.6760864
Camp near 11,180-ft. Devils Thumb Lake; charge up to Continental Divide past summer snowfields for monster views. Next day, descend to bus stop (last bus leaves @ 11 p.m.)
Mountain views
Location: 39.9660037, -105.6329441
Heading into the Jasper Creek drainage, a meadow opens to views up the valley. ©Peter Matranga