Cottonwood Lake has a reputation as the quintessential Crazy Mountain hike. Why? It's got everything: a rugged cirque setting, granite peaks, and far fewer people than the trails closer to Bozeman. The trail follows Cottonwood Creek through thick forest and open meadows, crossing the creek several times along the way. The first couple miles follow an old jeep road. Don't get too comfortable, because the real climbing starts after that. Once you break above treeline, the views open up and the granite walls of the cirque come into full view. Plan to spend time at the lake eating lunch, exploring the shoreline, and if it's warm enough, taking a dip.
From Bozeman, head north on MT-86 N (Rouse Ave) for about 37 miles. Turn right onto US-89 S and drive 1.8 miles, then turn left onto Horse Creek Road near Wilsall. Follow Horse Creek Road for about 10 miles, then turn left onto Upper Cottonwood Creek Road. Continue for about 8 miles to the trailhead at the end of the road.
Don't let the first two miles fool you. The trail starts on an old jeep road with a gentle grade, but after that, it climbs steeply for about a mile before leveling out into alpine meadows. The final push to the lake involves more elevation gain through rocky terrain. Multiple creek crossings and the sustained elevation gain make this a challenging hike. Come prepared with sturdy footwear and trekking poles.
Between the elevation gain and the creek crossings, this isn't a trail you'll cruise through. Expect to average about 1.5 mph, putting you at the lake in roughly 3 hours. Budget at least an hour at the top. You'll want it for lunch, photos, and maybe some fishing. Call it a 6-7 hour day.
You start at about 6,800 feet and end at the lake around 8,900 feet. The climb is steady with a few steeper pitches, particularly after you leave the old jeep road.
Cottonwood Lake delivers. Granite walls rise straight out of the water, the cirque feels remote and wild, and you'll likely have it to yourself. The lake holds cutthroat trout, so bring your rod. Spend an afternoon here and you'll understand why locals love the Crazies even when the Gallatins and Absarokas get all the attention.
Cottonwood Creek parallels the trail for most of the hike, and you'll cross it several times. Water purification opportunities are plentiful, and you'll end at a lake.
You'll burn serious calories on the climb, so pack accordingly. Bring a real lunch, something you'll actually look forward to eating at the lake, plus snacks for the trail. There's nothing between Clyde Park and the trailhead, so stop in town if you need to grab anything.
The trail is generally well-defined but sees less maintenance than more popular routes. Expect several creek crossings that can be tricky during peak snowmelt in early summer. The Crazies get significant snow, so this hike is best attempted from late June through September. Early and late season hikers should be prepared for snow at the lake.
Dogs are welcome. There's plenty of water and shade for your pup, but the creek crossings and rocky terrain mean this isn't ideal for dogs who aren't comfortable with rough trails.
Cottonwood Creek Road is a long, winding gravel road. While passable for most vehicles in dry conditions, high-clearance is recommended. The final stretch to the trailhead can be rough.
Beartooth Publishing's Crazy Mountains Map covers this whole trail as well as some roads leading to the trailhead.
The trailhead has a small parking area that can fill up on popular summer weekends. Get there early to nab a spot, especially during hunting season.
No facilities at the trailhead. Plan accordingly before leaving Clyde Park.
While Hyalite fills up and the Bridgers get picked over, the Crazies stay quiet. The drive keeps most people away. You might see a handful of other hikers on a summer weekend. On a weekday, you could have the whole lake to yourself.
Creek crossings are part of the deal here. Bring water shoes or sandals to change into, and consider trekking poles for balance. The weather can change quickly at elevation, so pack layers and rain gear even on sunny days.
Footwear: Hiking Boots
Mosquitoes can be thick near the creek and lake, especially in early summer. Bring bug spray.
The lower portion of the trail winds through dense forest with good shade. As you climb higher, you'll hit open meadows and eventually get above treeline where there's little cover.
Don't count on any cell service from the time you leave the main highway. Download maps and let someone know your plans before heading out.
Why rush back? Cottonwood Lake makes a great overnight. Established campsites dot the area near the lake, and waking up to that granite cirque is worth the extra weight in your pack. The cutthroats bite in the evening, so bring your rod and a Montana fishing license.
Campfire Lake Loop
Strong hikers can connect Cottonwood Lake to Campfire, Moose, and Glacier Lakes for a challenging multi-day loop through the heart of the Crazies.
Grasshopper Glacier
From the lake, experienced scramblers can continue up toward Grasshopper Glacier for bigger views.
Plug 8.2 miles and 2,100 feet of elevation gain into our free hiking time calculator for a personalized estimate.