Tongue River Reservoir State Park

Decker, Montana
Established 1996
1,790 acres

Tongue River Reservoir State Park is a scenic eastern Montana park centered on a large reservoir known for boating, fishing, and wildlife viewing. Rolling prairie, cottonwood-lined shorelines, and open water create a quiet setting for camping, picnicking, and year-round recreation.

Entrance Fee

Free

Visiting with Dogs

Dogs allowed; keep on leash, clean up after pets, and follow posted rules. Check seasonal restrictions before visiting.

Visitor Tips & Reviews

What Visitors Say

Quiet reservoir park loved for boating, fishing, camping, birdwatching, and wide-open views. Visitors praise peaceful sunsets, spacious sites, and a relaxed, uncrowded atmosphere.

Tips from Visitors

  • Bring insect repellent for mosquitoes near the water.
  • Check wind conditions before boating or paddleboarding.
  • Pack extra drinking water and sun protection.
  • Use designated campsites and follow posted fire rules.
  • Watch for sudden weather changes on the reservoir.
  • Keep pets leashed and clean up after them.

Best Time to Visit

The best time to visit Tongue River Reservoir State Park is late spring through early fall, when warm weather makes boating, camping, and shoreline fishing most enjoyable. Spring and fall often bring fewer crowds and active wildlife.

Amenities

RestroomsParkingPicnic AreasBoat RampCampingFishing AccessVault ToiletsDrinking WaterDump StationDay-Use Areas

Nearby Attractions

Explore these attractions near Tongue River Reservoir State Park:

  • Tongue River Reservoir
    The reservoir itself is the main attraction, offering boating, fishing, and wildlife viewing along miles of shoreline.
    Within the park
  • Decker Schoolhouse Museum
    A small local history stop that reflects the ranching and community heritage of the Decker area.
    2 miles away
  • Bighorn Canyon National Recreation Area
    A dramatic canyon and lake landscape with scenic overlooks, boating, and hiking opportunities within a reasonable drive.
    55 miles away

Things to Do at Tongue River Reservoir State Park

FishingBoatingCampingBirdwatchingPicnicking

Camping at Tongue River Reservoir State Park

Tent and RV camping available with hookups, restrooms, showers, picnic areas, and reservoir access; reservations recommended in peak season.

Hiking Trails

Tongue River Reservoir State Park offers easy, scenic day hiking with gentle trails and shoreline views that are popular with families and casual walkers. Reviews often mention peaceful water access, birdwatching, and open prairie scenery rather than challenging terrain. Trails are generally straightforward and best for a relaxed outing, especially in spring, summer, and fall when the weather is mild.

Tongue River Reservoir Shoreline Trail

Easy

A scenic lakeside route with broad reservoir views, birdwatching opportunities, and access to picnic and day-use areas.

4.5 mi
1.5-2.5 hours
150 ft gain
Easy difficulty

North Shore Loop

Easy

A gentle loop along the north side of the reservoir with open water vistas, cottonwood areas, and frequent wildlife sightings.

3.2 mi
1-2 hours
100 ft gain
Easy difficulty

South Bay Access Trail

Easy

A short, relaxed trail connecting shoreline access points and quiet coves, ideal for a casual hike or family outing.

2.8 mi
1-1.5 hours
80 ft gain
Easy difficulty

Reservoir Overlook Trail

Moderate

A slightly steeper trail leading to elevated viewpoints over the reservoir and surrounding prairie landscape.

2.1 mi
1-1.5 hours
220 ft gain
Moderate difficulty

Directions

From Decker, drive north on Tongue River Road about 2 miles, then follow park signs to the reservoir access areas and campground.

Frequently Asked Questions

What are the main things to do at Tongue River Reservoir State Park?

Visitors commonly come for boating, fishing, swimming, picnicking, and camping. Many reviews mention it as a quiet place to relax on the water, especially for fishing and enjoying lake views.

Is the water good for swimming and boating?

Yes, many visitors use the reservoir for swimming and boating in warmer months. Conditions can vary with wind and water levels, so boaters should check weather and be prepared for changing lake conditions.

What kind of fishing can I expect there?

Fishing is one of the park’s most popular activities. Anglers often target species common to Montana reservoirs, and reviews frequently mention good shore and boat fishing. Success can vary by season and water conditions.

Are there camping facilities at the park?

Yes, the park offers camping, and visitors often describe it as a peaceful, low-key place to stay. Amenities may be simple compared with larger parks, so it’s a good idea to check current site and facility details before arriving.

Is Tongue River Reservoir State Park crowded?

It is often described as less crowded than many larger state parks. Reviewers like the quieter atmosphere, especially on weekdays. Summer weekends can still be busier, particularly near the water and popular camping areas.

What should I know before visiting?

Bring supplies, sun protection, and water, since services may be limited. Wind can affect boating, and weather can change quickly. Many visitors recommend checking current conditions and park alerts before heading out.

Location
camping and backpacking gear

Don’t Forget the Essentials

Essential camping & hiking gear we recommend to make your park trip easier and more comfortable.

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