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Betasso Preserve



6.7 mile 10.7 kilometer loop
94% Runnable


Ascent: 776' 237 m
Descent: -778' -237 m
High: 6,575' 2,004 m
Low: 6,178' 1,883 m


Avg Grade: 4% (3°)
Max Grade: 16% (9°)


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Trail shared by Duncan Moore

This run is easily accessible from Boulder and offers amazing singletrack with beautiful views.

Duncan Moore

Features Birding · Fall Colors · Views · Wildflowers · Wildlife


To access, drive up Boulder Canyon turning right up Sugarloaf Road. Take your first right up Betasso Road. Once on Betasso Road you'll see parking for the trailhead on your left.

Need to Know

Recommended use Wednesdays and Saturdays due to mountain bike closure. If you choose to run on a day that bikes are allowed, it is recommended to pay attention to the direction of bike traffic, which is posted and run against bike traffic. This makes visibility for both parties better. Always be courteous to everyone using the trail.

Runner Notes

This route features smooth, hard-packed dirt with occasional rocks and roots.


The trailhead offers a bathroom, picnic area, and plenty of parking. Unfortunately there is no access to drinking water.

The Canyon Loop opens up to a fork in the road. The trail is one giant loop and either direction is appropriate for travel.

Canyon Loop Trail totals 3.3 miles and begins on the rim of the preserve. The first half of the trail quickly drops in altitude and the second half of the trail is spent gaining altitude. The trail is mainly comprised of singletrack and has numerous opportunities for amazing views. The trail is made up of compact dirt with some rocks and roots showing.

Near the half waypoint of the Canyon Loop, the Benjamin Trail Link intersects. This is 0.75 miles of singletrack that brings you directly to the Benjamin Loop. The Benjamin Loop is by far the best part of this run offering 2.4 miles of heavily forested singletrack. The trail has similar signage as the Canyon Loop dictating direction of travel for bicycles. The trail is comprised of a series of switchbacks that gradually climb up the rim and then descend into another series of switchbacks. The trail is hard compact dirt with a bridge feature.

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Nov 17, 2019
Erik Funk
Aug 31, 2019
Levi Perigo
Two laps CW
Aug 24, 2019
Levi Perigo
Jul 29, 2019
Toko Morimoto
Jul 5, 2019
Allison Torpey
Got scared. 2mi — 20h 00m
May 13, 2019
Chad Carter
6.7mi — 1h 10m
Apr 28, 2019
Georgina B
amazing run with a great variety of scenery! Lots of singletrack switchbacks (especially during the Benj Loop section). Sunday open to mountain bikes — 11h 30m
Apr 13, 2019

Trail Ratings

  4.1 from 61 votes


  4.1 from 61 votes
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in Colorado


163 Views Last Month
10,155 Since Jan 29, 2015



Cruising along Benjamin Loop, look off to the side to enjoy great views.
Apr 2, 2017 near Boulder, CO
The meadow
Oct 20, 2015 near Boulder, CO
Progression of the Betasso climb in three shots.
Aug 25, 2017 near Boulder, CO
Arriving at the Benjamin loop from the connector.
Oct 20, 2015 near Boulder, CO
The trail is smooth and wide through the trees to finish the Canyon loop.
Oct 20, 2015 near Boulder, CO
The climbs are gradual.
Dec 21, 2018 near Boulder, CO


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