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Wheeler Geologic Area to Halfmoon Pass



20.4 mile 32.8 kilometer loop
87% Runnable


Ascent: 3,674' 1,120 m
Descent: -3,676' -1,120 m
High: 12,474' 3,802 m
Low: 10,393' 3,168 m


Avg Grade: 7% (4°)
Max Grade: 24% (13°)


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Trail shared by Caroline Cordsen

Experience a twenty-mile excursion exploring the volcanic remnants that helped to shape the San Juan Mountains.

Caroline Cordsen

Features Birding · Commonly Backpacked · River/Creek · Views · Wildlife

Wheeler is open year round, but usually snowed in until May. No camping or campfires are allowed inside the area of the formations, though you can find great dispersed camping at both the Hanson Mill site and at the end of Wheeler Road #600.


Violent eruptions, and the searing heat of molten lava; ash piled thousands of feet high. Carved out from the heart of the La Garita Caldera deep within the San Juan Mountains, the ghostly hoodoos of Wheeler Geologic Area are the end result of one of the world’s most catastrophic known volcanic eruptions.

Second only to Pikes Peak, Wheeler was once a highly trafficked tourist destination back in the 1800s when it held the designation of Colorado’s first national monument. But having long since been stripped of its title, now the journey out is just as laborious as its illustrious history.

Need to Know

Crossing East Billows Creek during the spring can be a dangerous affair with the snowmelt-filled banks.

Use care heading up to Halfmoon Pass during summer afternoons, and be weary of incoming thunderstorms.

When snow-free, an ATV or modified high-clearance vehicle is recommended on the 4X4 road leading into Wheeler.


Forging out from the parking lot, the striking lack of green telltale of a beetle-infested forest will catch you off guard. As beautiful as the woods are today, it’s heartbreaking to imagine their past glory days. Signs navigate between the two options of reaching the geologic site: a very rough, fourteen mile 4X4 drive, or a seven and a half mile run. Opting for the latter, the trail begins on a rather flat route through the woods until the flora opens up to views of the volcanic cliffs surrounding East Billows Creek. Crossing the raging snowmelt-filled banks, the trail then takes its lead from East Billows, traversing a loose scree field below Canyon Nieve before breaking into three miles of easy climbing with amazing views of the rolling meadows below Fish Canyon Tuff. Nearing the crest, the forest’s namesake La Garita Mountain (13,710 ft) comes into view before the trail drops again to meet up with the 4X4 road. The final stretch into Wheeler is an easy downhill jaunt along the battered road. A three mile loop skirts the geologic area, while another mile on the main trail will pull you up to Halfmoon Pass for an amazing bird's-eye view.

Flora & Fauna

The usual deer, elk, and bear can be seen along the route. Much of the route travels through beetle kill.

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Trail Ratings

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  4.5 from 4 votes
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in Colorado


50 Views Last Month
2,686 Since May 12, 2017



The beetle kill is wide reaching in this corner of the San Juans.
May 12, 2017 near Creede, CO
The ghostly hoodoos of Wheeler Geologic Area look to me like a slice of Bryce Canyon, Utah was scooped up out of the earth and plopped right down into the middle of the San Juans.
May 12, 2017 near Creede, CO


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