Louise Lake

7.2 mi round trip 1,305 ft gain Moderate 74 Miles from Bozeman, MT. 94 Minutes
Louise Lake with deep blue-green water framed by spruce trees and rocky peaks
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Should You Do This Hike?


Best for Anglers and lake hikers willing to make a Tobacco Root day trip for large cutthroat in a quiet setting
Not ideal for Anyone driving a standard car — the last 2 miles of road to the trailhead require high-clearance
Time required About 5 hours round trip, 94 minutes from Bozeman
Key highlight Large Westslope cutthroat trout in clear water, one of the better fishing lakes accessible by a day hike from Bozeman
Dogs Friendly
Bathroom No — plan ahead

The Short Version


Louise Lake is a 7.2-mile round trip in the Tobacco Root Mountains, 74 miles from Bozeman. The trail is gradual and straightforward, but the last 2 miles of road to the trailhead require a high-clearance vehicle. The main attraction is the fishing: Louise Lake holds large Westslope cutthroat in clear water surrounded by spruce and rocky peaks. Medium traffic, limited parking, no bathroom at trailhead.

Why Louise Lake


Louise Lake is primarily a fishing trip that happens to involve a good hike. The lake holds large Westslope cutthroat, the water is clear, and 10,353-foot Middle Mountain is visible to the south. For hikers who fish, it is hard to beat the combination.

The Tobacco Roots don't get the foot traffic of the Gallatins or Bridgers, which means the trail stays quiet even on summer weekends. The rough road to the trailhead does its part to discourage casual visitors, and the result is a lake that feels remote for being less than 2 hours from Bozeman. Bring your Montana fishing license, a snack for the lake, and plan on spending time at the water.

What Most Guides Don't Tell You


Parking Scarce

There are a couple of trails that start from this small parking lot, so spaces might be scarce.

Bathroom No

There's an outhouse and a vault toilet past Mammoth along the dirt road leading up to the trailhead.

Crowds Medium

An easy, scenic hike with great fishing usually means heavy foot traffic, but this is not the case for Louise Lake trail. The distance from popular tourist destinations and the extremely rough road keeps the traffic down to an enjoyable level.

Road Access Four Wheelin'

The last two miles of road leading up to the trailhead are best traveled by a high-clearance vehicle. If you only have a car you might consider parking down the road and walking the last two miles up to the trail.

Cell Service Spotty

Verizon picks up a few bars at the Lake, but you will not have service for the majority of the hike/drive.

Dogs Friendly

Frequent water and shade make this a great hike for most dogs.

Getting There


74 Miles from Bozeman, MT. 94 Minutes

From Bozeman head west on I-90. Follow I-90 W for about 50 miles to MT-2 E/MT-359 in Cardwell. Take Montana Highway 359 south for approximately five miles to South Boulder Road. Travel south for approximately 15 miles to the trailhead at Bismark Reservoir.

More Details


Water Frequent

This trail intersects a creek several times throughout the hike and ends at a lake.

64 oz consumed per person

Trail Conditions Good

The wide dirt trail is well beaten and easy to find.

Clothing & Footwear

There is a nice mix of shade and sun on this trail. Shorts and a t-shirt would be fine in the warmer months because you won't be trekking through any tall grass on the trail. Consider bringing a swimsuit and towel just in case you feel like going for an icy dip in the lake.

Footwear: Tennis shoes are OK on this hike

Food

This is a short hike and food is not required, but you might consider bringing a small lunch or snack to eat up at the lake.

Bugs Light

In the thicker parts of the trees and near the lake you may experience a light amount of mosquitoes and flies.

Shade Moderate

A nice mix of shade and sun.

Overnight Yes

Along the road south of Mammoth there are quite a few car camping spots. Additionally, up at the lake there are some well-used tent spots if you're interested in backpacking.

Trail Connections

None.

Map

Beartooth Publishing's map of the Tobacco Root Mountains covers this hike and part of the drive.

Best Time to Go


Late June through September. The Tobacco Roots get snow and the last 2 miles of road to the trailhead require high-clearance, which is harder to navigate in wet conditions. The fishing is good across the summer once the lake opens up.

Peak Season

July through August: trail clear, lake fishing active for Westslope cutthroat, mild temperatures in the basin, no snow on the approach.

Shoulder Season

Late June and September: June has possible snow at the trailhead elevation, September is cool and quiet with good fishing into the shoulder season.

Avoid / Off Season

Before mid-June: snow can block the upper trail and the rough access road is more difficult in wet spring conditions.

Tips Worth Knowing


  • The last 2 miles of road to the trailhead require high-clearance. If you are driving a standard car, consider parking where the road gets rough and walking those final miles.
  • Bring your Montana fishing license. Louise Lake holds large Westslope cutthroat in clear water. The evening bite near the inlet is typically the most productive.
  • Verizon picks up a few bars at the lake itself, but you will be out of service for the majority of the hike and drive. Download maps before leaving Cardwell.
  • An icy dip in the lake is worth it on a warm day. The water is cold and clear. Bring a small towel.
  • The rough access road keeps casual visitors away. Medium trail traffic here means a fraction of what similar Hyalite trails receive.

How It Compares


If you want an alpine fishing lake closer to Bozeman Emerald and Heather Lakes Two lakes with different fish species 21 miles from Bozeman, 11-mile round trip, shorter drive and more established trail
If you want a demanding lake hike without the rough access road Lava Lake 47-acre swimming lake in the Gallatin Canyon with a well-maintained road, 6.5-mile round trip, easy highway turnoff
If you want a remote lake in the same Tobacco Root spirit Spanish Lakes Spanish Peaks Wilderness, 14-mile round trip, remote alpine lake with similar fishing and solitude profile

Frequently Asked Questions


Do I need a high-clearance vehicle to reach Louise Lake?

For the last 2 miles of road to the trailhead, yes. The road becomes rough and rutted. If you have a standard car, park where the road gets difficult and walk the extra distance in. It is about 2 additional miles each way.

How is the fishing at Louise Lake?

Very good for Westslope cutthroat. The lake is known for holding large fish in clear water. Bring your Montana fishing license and a lightweight rod. Evening fishing near the inlet is most productive.

Is there a bathroom at the trailhead?

No bathroom at the trailhead itself. There are an outhouse and a vault toilet along the road before Mammoth, on the way in.

Can you swim in Louise Lake?

Yes. The water is cold, clear, and deep enough to swim. Bring a towel. Warmer afternoons in July and August are the best time.

Is the trail suitable for families?

Yes, the trail is described as family-friendly with gradual switchbacks and a well-beaten path. The 7.2-mile distance is the main consideration for younger hikers. The rough access road is the bigger logistical hurdle.

How long will this hike take you?

Plug 7.2 miles and 1,305 feet of elevation gain into our free hiking time calculator for a personalized estimate.

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