Sourdough Trail (South)

Trail Meter: 

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.


Trail Meter: Fair»Good

Great condition right now

Trail Meter: Poor»Fair

A few spots with water flowing and a couple muddy spots at the north end. All rideable.

Trail Meter: Good»Poor

Starting from the south end I made it 2 miles before getting turned back by drifts.

Trail Meter: Fair»Good

Mostly rideable on a Fat.
Some softer spots midway between Rainbow lakes lot and Brainard.
Use low tire pressures to keep the float.

Soft slippery snow. Lower section isperfect on a fatbike. Softer and less packed after the bridge.

Soft slippery snow. Lower section if perfect on a fatbike.

Trail Meter: Good»Fair

A few inches of fresh pow on a packed base.

great fat bike conditions, rideable on a crampus. may not be normal mtb-able

Trail Meter: Fair»Good

Awesome fatbike conditions!! 2 inches of fresh on good base!

Trail Meter: Poor»Fair

condition set to Fair

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