Sourdough Trail (South)

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Sourdough South is a rolly polly lungbuster, traveling north-south and paralleling (but nowhere near) the Peak to Peak Highway.  Solitude and suffering await you... ok, it's really not that bad if you're mentally prepared for high altitude riding with some loose rocks thrown in there.

You can start this trail from the south at the CU Research Center / Rainbow Lakes trailhead, and from the north at the Brainard Lake trailhead. If you cross Brainard Lake Road, then the Sourdough trail continues - we call that section Sourdough North because this section of trail has a pretty different character from Sourdough South.

Sourdough Trail (South) GPX File142.45 KB
Sourdough Trail (South) Google Earth File5.28 KB
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Sourdough Trail (South) Click on image to enlarge
Sourdough Trail (South) Click on image to enlarge

T: 6 A: 7 C: 6

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5.9 mi.
1350 ft.


a few muddy spots at the bottom; mostly dry or tacky from recent rains.

Mainly dry. Some splashy mud sections.

Running well.

all good, enjoy!

The lower 4 miles were dry. I'm assuming the upper 2 miles were also dry.

Deep snow drifts from before Peace bridge to Brainard road.  Will need a few weeks to melt.


Rode there on 2/11. Snow was deep and soft, but centerline was mostly rideable. Ride on the fattest of fat bikes and you'll probably have a great time!


Open to fatbiking. Skinny tires need not apply.

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