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Trespass to Cottonwood Creek Loop

  5.0 ( 1 ) Favorite


23.1 mile 37.1 kilometer loop
75% Runnable


Ascent: 6,840' 2,085 m
Descent: -6,844' -2,086 m
High: 10,645' 3,244 m
Low: 6,719' 2,048 m


Avg Grade: 11% (6°)
Max Grade: 44% (24°)


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Trail shared by samh Haraldson


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A loop combining multiple gorgeous drainages of the Crazy Mountain Range.

samh Haraldson

Features Birding · Lake · River/Creek · Views · Wildflowers · Wildlife


The Crazy Mountain Range consists of many out-and-back running trails but with the addition of a relatively benign off-trail section a long loop connecting the Trespass Creek Trail , Sweet Grass Trail, and Cottonwood Lake drainages can be formed.


Starting at the Trespass Creek Trail/Cottonwood Lake trailhead, run up Trespass Creek. Along this wide open basin enjoy the unique geology, flora, and fauna of the Crazy Mountain Range which sits stoically at the far Eastern Front of the Rocky Mountains and takes the brunt of the brutal winds from the expansive plains to the East.

From the head of Trespass Creek drop down the Middle Fork of Sweetgrass Creek toward the popular Campfire Lake. Here many camping options exist as well as fishing and day trip exploration potential.

Next up is to follow the Sweet Grass Trail a bit further before heading up the South Fork of Sweetgrass Creek. A rocky, gorge with waterfalls is sided by wide open mountain meadows. Peaks tower to the left and right of you. At this headwaters find Glacier Lake and an optional side trip that takes you to the top of Conical Peak. Or, if that's not your fancy simply proceed off-trail on a low-class scramble to the col formed between Sweetgrass and Cottonwood Creeks.

From this col descend toward Cottonwood Lake alongside Grasshopper Glacier where you'll find more excellent camping or the option to continue on making your way back to your vehicle at the bottom of Cottonwood Creek. This section of trail is somewhat popular with runners so you'll be sharing the trail but in true SW Montana fashion a friendly wave and a "so, how was the fishing?" will go a long way.

History & Background

The article I am editing said, under description, that you go up the North Fork of Sweet Grass Creek to get toward Glacier Lake. It is the South Fork. Also, in the same paragraph, it mentioned "cool" when it meant "col " I made these corrections

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We need help with the following missing trail information:

Need to Know, Flora & Fauna, Runner Notes


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Aug 3, 2019
Corinne Moss
we missed the fork to head towards trespass Creek and started at cottonwood Creek instead, which I think is the way to go. the first steep ascent a… 23.1mi

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  5.0 from 1 vote


  5.0 from 1 vote
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Granite Peak from the South ridge of Conical Peak.
Apr 22, 2015 near Big Timber, MT
Apr 22, 2015 near Big Timber, MT
Glacier Lake
Apr 22, 2015 near Big Timber, MT
Sweetgrass Creek drainage
Apr 22, 2015 near Big Timber, MT
Old tree in the Cottonwood Creek drainage of the Crazies.
Apr 22, 2015 near Livingston, MT
Campfire Lake
Apr 22, 2015 near Livingston, MT


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