Central Montana Hikes & Attractions

Crystal Lake in Montana’s Big Snowy Mountains

Crystal Lake offers camping, hiking, and fishing located in an island of wild mountains surrounded by prairie. The lake is in the Big Snowy Mountains which are one of the small “island” ranges that dot central Montana. The mountains are south of Lewistown, MT, and offer camping, fishing, hiking, and backpacking.

Nearest CityLewistown, MT – 31 miles
SeasonAccess road closed from late Fall until early June
Camping – Early June to Labor Day
AttractionsHiking, Camping, Fishing, Boating, Birdwatching
ManagementHelena-Lewis & Clark National Forest
Elevation5,700 ft
FeesNo day-use fee
2022 Nightly camping fee – $20.00

2023 Information

  • Major closure! From July through early November, the Ice Cave Trail, Crystal Lake Cabin, Crystal Lake Campground, and Crystal Group site will be closed for major work. Other trails remain open along with lake access and day use.
  • Lake Use – Free
  • Picnicking – Free
  • Planned Fish Stocking
    1,000 – 9″ Westslope Cutthroat Trout
    500 – 12″ Rainbow Trout

Crystal Lake and the Big Snowy Mountains are part of the Helena – Lewis & Clark National Forest and are one of the “Island” mountain ranges that are scattered in Central Montana. The Big Snowies extend as much as 10 miles north to south and 25 miles east to west. The highest peaks are at 8,600 ft and there are many miles of ridgeline that can be followed at 8,000 ft or higher.

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Directions to Crystal Lake

Crystal Lake is quite easy to find. From Lewistown MT, take US Highway 87 north 8.7 miles to the Forest Access sign (Crystal Lake Road). Turn left onto the graveled Crystal Lake Road and go about 5 miles to a Y intersection. Bear left and go 4 miles to the Recreation Area sign. Turn left at the sign, and continue on Crystal Lake Road for nearly 13 miles to the campground. The Crystal Lake Road begins as a well-maintained two-lane gravel road. As you approach the mountains the road narrows and the last 6 miles are single lane and paved. 

If you are coming from Harlowton or points south Crystal Lake is easy to find. There is a well-signed turn on US 191 that heads east. Just follow the signs until you reach the intersection with the road from Lewistown and turn south (right) and continue on to the lake. It seems odd that the lower sections of the road would be gravel and the upper paved. However, the last nearly 6 miles are single lane and are steep and twisty in places. There is a steep drop-off right at the edge of the road so be sure to drive safely on this section.

Understanding Crystal Lake

Crystal Lake itself is very interesting. It is a 45-acre lake at about 5,700 ft elevation. Crystal Lake is a natural feature that is very shallow. The maximum depth is no more than 15 ft when it is full. The Lake is fed by snowmelt from the surrounding mountains. The Big Snowy Mountains get good winter snows but no consistent rain in the summer, so, little water enters the lake after it fills from melting snow.

Crystal Lake sits on a rock layer of porous limestone and water seeps out of the bottom of the lake all year long.  Although the lake fills with winter snowmelt, by late summer the water level falls dramatically. By fall the lake is little more than a large shallow pond. The open water is far from the shoreline and a broad expanse of soft mud surrounds the lake.

Camping at Crystal Lake

The Crystal Lake Campground is a typical USFS campground. It’s laid out in a single large loop with campsites located on both the inside and outside of the loop. There are about 28 campsites total and most sites are fairly close together. However, there is more privacy than at some campgrounds and a few sites are somewhat isolated. (I have not visited the campground recently but reports are that it is less private after a tree removal project.) Each site has a picnic table and a circular steel fire pit. If you are new to camping we have advice on Selecting A Campsite.

The Crystal Lake Campground has water available seasonally but don’t count on it early in the season or in the fall.  The campground is suitable for all types of camping – tents, trailers, or RVs and several sites are accessible. The USFS charges a camping fee during the peak summer months.

In addition to camping, the Crystal Lake Cabin is available to rent by the night. This one-room cabin is suitable for up to 4 people and provides a great experience for those who want to enjoy the area without camping. The USFS offers this type of cabin rental wherever it is practical.

In 2017 the USFS closed the Crystal Lake Campground for a year while they removed hazardous trees. There are reports that the campground is not nearly as forested as it was previously.

Photo of a lone photographer on the shore of Crystal Lake
In the fall of the year the water level in Crystal Lake falls very low. The water in the lake has slowly seeped out through the limestone bottom and the water is far from the edge of the lake. Here a photographer seeks to get a photo of a mature Bald Eagle feeding on the fish in the lake.

Fishing Crystal Lake

Crystal Lake is so shallow in the winter that it typically freezes solid, killing any fish that are in the water. Consequently, Montana Fish, Wildlife & Parks stocks rainbow trout into the lake every year. The stocked fish are usually about 12 inches in length and grow quickly in the fertile lake. The FWP management plan calls for Crystal Lake to receive 1,000 12 inch fish every year which can provide excellent fishing.

The lake is located in Montana’s central Fishing District and standard fishing regulations govern the lake.  To learn about the fishery resource and any management changes to Crystal Lake visit Montana Fish, Wildlife & Parks.

Crystal Lake is open to all types of non-motorized boating. There is a boat ramp and beach area. The lake is perfect for kayaks, canoes, and stand-up paddleboards. Swimming is popular during the summer months and is often a family activity.

Birdwatching and More

With water leaking out of the lake bottom all summer the lake gets smaller and very shallow. As this happens the trout become very vulnerable to predatory birds. Although there are patches of aquatic vegetation, the shallow clear water makes it almost impossible for the trout to hide successfully. This makes for great bird watching opportunities and Crystal Lake in the fall can be an excellent place to view Bald Eagles.

Photo of bald eagle sitting in a dead tree
Crystal Lake is a frequent gathering spot for bald eagles in the fall. The lake has become very shallow and the trout are much more available to the eagles and other predators.

There is an interesting hiking trail that winds around Crystal Lake. This trail is about 1 3/4 miles in length and has very little elevation change. It is a great trail for almost anyone and alternates between forest and open areas. Benches that overlook the lake are located at several spots that provide places to take a break and enjoy the scenery. This is a great trail for bird watchers, photographers, and other nature lovers.

Hiking in the Big Snowy Mountains

The primary loop hike into the Big Snowy Mountains begins and ends at Crystal Lake and is officially recognized as the Crystal Lake National Recreational Trail. This trail begins and ends right in the campground. The hike is about 12 miles in length and starts with a tough 2,000 ft climb in the first three miles. After you reach the top it’s easy hiking along the mountain tops. Be sure to take the side hike down to the Snowy Mountain Ice Cave to explore an unusual feature. There is no water available on this hike so take all you need with you.

There is a well-developed trail system that runs through the Big Snowies. Unfortunately, there are only a few options for access. The US Forest Service (USFS) has forest maps that show trails and accesses. Another good option is the DeLorme Montana Atlas & Gazetteer.

Several years ago the Forest Service put out a Crystal Lake Area Trails brochure that can be helpful. I don’t think this is available any longer but the link is to a PDF of the brochure. You can find a full description of this hike as well as about 100 others in the book Hiking Montana which I highly recommend.

The Big Snowy Mountains are overlooked by many but they offer a lot of great recreation opportunities. Especially for those looking for an off-the-beaten-path location. If you have the chance to explore the Big Snowies you will not be disappointed.

Where is Crystal Lake?

Crystal Lake is in the Helena – Lewis & Clark National Forest southwest of Lewistown, MT.

Is there an entrance fee at Crystal Lake?

No, it is free to visit Crystal Lake for all activities except camping. There is a $20.00 nightly camping fee for 2022

Is there good fishing in Crystal Lake

Generally, there is good trout fishing in Crystal Lake. Montana FWP stocks Crystal Lake every year and fishing is best earlier in the year when water levels are the highest.

Can I reserve a campsite in advance?

No, there is no reservation system for Crystal Lake. All campsites are first-come-first-served.

What is the open season for Crystal Lake?

Crystal Lake is open year-round but the access road is closed to vehicles until early May. The campground is open from early June to late September.

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