Blue Lake is the most popular hiking destination in the Crazy Mountains for good reason. Sitting at 8,282 ft in a valley between Granite Peak and Crazy Peak, Blue lake is connected to the larger Granite Lake and the smaller Thunder Lake. The hike to Blue Lake is less than 4 miles on good trails with an elevation gain of about 2,200 ft.
Directions to the Blue Lake Trailhead
The hike to Blue Lake begins at the Big Timber Creek trailhead near the Halfmoon Campground. This popular trailhead is the beginning point for day hikes to Twin Lakes and serves as the starting point for many backpacking trips into the Crazies.
The trailhead is at the end of the Big Timber Canyon Road which intersects with US 191 about 11 miles north of Big Timber, MT. There are signs in both directions on US 191 and Big Timber Canyon Road runs west toward the Crazy Mountains. Follow this gravel road for about 2 miles until a signed junction where you bear to the right. Continue on for about 10 miles until the road ends at the Halfmoon Campground and the Big Timber Canyon trailhead.
The Big Timber Canyon Trail – Trail 119
The trail to Blue Lake follows Big Timber Creek upstream for the first 3 miles. The trail is an old roadbed so it’s wide and fairly level. However, in places it’s rocky so hiking is not always easy. About 1/8 mile from the trailhead there’s an unmarked side trail to the left which leads to Big Timber Creek Falls. The falls are an impressive sight and this short side trip is worth taking.
The trail stays wide and easy to follow. There are two Big Timber Creek crossings and each has a large sturdy bridge so there is no concern for hikers. Big Timber Creek is a popular whitewater destination for extreme kayakers and you might find them enjoying the rushing waters. If you’d like to learn more about the whitewater be sure to read our page about Big Timber Creek Falls.
About 2 miles from the trailhead the trail crosses Big Timber Creek and climbs the hillside. After climbing about 50 ft you cross a large patch of bare rock with great views to the south. From here you can spot Thunder Rapids plunging down the mountainside. Thunder rapids is the outlet of Thunder Lake which is connected to Blue Lake. There is no easy way to get to Thunder Rapids so be sure to enjoy the view from here.
Blue Lake Trail – Trail 118
After hiking a little over 2 1/2 miles and climbing 1,300 ft you reach the Blue Lake Trail (#118) at a large, well-signed intersection. The Blue Lake trail heads to the south while the main trail continues on for about a mile to Twin Lakes then on to the interior of the Crazy Mountains.
The Blue Lake trail heads down a short distance to a Big Timber Creek crossing. Unfortunately, there is no bridge here so you have to find your own path across. At lower flows, it’s easy to scramble across on deadfall but at high water, this can be a difficult crossing.
From the creek, it’s a steady climb up a series of switchbacks that quickly climb the mountainside. The trail stays steep for about a half mile then flattens a bit. After about 3/4 mile the trail reaches two small ponds and a couple of old cabin foundations. It must have been quite an experience living up here!
Blue Lake and Granite Lake
Past the ponds, the trail climbs slowly and dramatic views of Granite Lake sitting below begin to appear. After about 1/3 mile, the trail gradually fades to nothing but the path is obvious – down the hill to the lake. The most logical route finds you reaching the bottom along the channel connecting Blue and Granite lakes.
When you reach the channel, Granite lake is to the right (west) and Blue Lake is to the left (East). Granite measures about 15 acres and has a maximum depth of about 95 ft. Much of the northwestern shoreline is steep rock leading up the side of Granite Peak. Blue Lake is about 11 acres and much shallower with a max depth of about 40 ft. and has mostly forested shorelines. Thunder Lake is more of an extension of Blue Lake as the channel between them never really narrows much. Thunder lake measures about 3 acres and is only about 8 ft deep.
After reaching the lakes most hikers choose to retrace the route back to the trailhead. When you rejoin the Big Timber Canyon Trail you’re only about a mile from Twin Lakes. If you have the time and energy, this is a great side trip to a very scenic spot.
Not everyone returns immediately after reaching Blue Lake. Backpackers often find this a great place to set up a camp to more fully explore the area. It’s easy to spend a few nights camped in such magnificent surroundings.
Things to do at Blue Lake
Blue, Granite, and Thunder lakes are closely connected and essentially share a self-sustaining population of rainbow trout. It’s believed that these fish were first introduced by a miner named Druckmiller in the 1920’s. They seem to thrive and all three lakes have healthy populations of rainbows that can grow to 15″.
While reaching the lakes is all the hike most people are looking for, there are two popular side hikes to enjoy.
Pear Lake is up the drainage that is to the southwest of the lakes. It sits at about 8,800 ft and its outlet stream feeds into Granite Lake near the channel to Blue Lake. Pear Lake is about 40 acres in size and, at 185 ft it’s the deepest lake in the Crazies. Fishing is good in the lake but there is no trail so you have to follow the feeder stream uphill by picking a path until you reach the lake. The rainbow trout are all planted by MT FWP and there is no natural reproduction. Check with FWP Pear Lake Info to find out the latest info if you plan to fish here.
Druckmiller Lake (sometimes called Druckenmiller) is the headwater lake for Big Timber Creek and it flows down into Granite Lake on the southern lakeshore. The lake is 24 acres and reaches a depth of nearly 100 ft. It sits at about 9,000 ft and can remain ice-covered until late July. The drainage coming down from Druckmiller is obvious but there is no trail to the lake. It’s up to you to find your own path. The snow and ice remain late here so be extra cautious.
As with Pear Lake, Druckmiller has good fishing for healthy rainbow trout. The lake depends on stocking so, for the best fishing, check with MFWP for the latest Druckmiller Lake stocking information. These high-mountain lakes receive very little fishing pressure so MFWP does not stock them frequently.
Granite Peak, Crazy Peak, Iddings Peak, and Big Timber Peak can all be climbed from a base camp in the Blue Lake area. Unfortunately, all of the land here is a mixture of public and private, and some of these peaks are on private property. In many places, the approach crosses private land. If you want to climb here you need to contact the Yellowstone Ranger District at 406-222-1892 to find out the latest access information.
Frequently Asked Questions
The Halfmoon Campground shares the entrance road with the trailhead. It’s only a couple hundred yards from campsite to trail.
The hike to Blue Lake is less than 4 miles and the trail gains about 2,000 ft. The trail is generally in good condition and mostly easy to hike.
There are a number of good backpacking campsites along Blue and Granite lakes. This is a special fire restriction area and no campfires are allowed – ever!