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4.4 miles
Distance
1,060 ft
Climb
-31 ft
Descent
01:06:29
Avg time
1,030 ft
Altitude change
6,396 ft
Altitude min
7,425 ft
Altitude max
6,396 ft
Altitude start
7,425 ft
Altitude end
4.5%
Grade
-6.2%
Grade max
30.1%
Grade min
4 miles
Distance climb
2,044 ft
Distance down
1,407 ft
Distance flat
01:06:29
Avg time
Trail Details
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Activities
- Mountain Bike
- Winter Fat Bike
- Horse
- Hike
- Trail Running
- Snowmobile
- Snowshoe
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Riding AreaLittle Blackfoot
Elliston, Montana -
Ref Number#65
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AKACottonwood Lake
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Difficulty Rating
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Local Popularity90 in Mountain Biking [+]
- 5 in Trail Running
- 5 in Hiking
- 5 in Horseback
- 5 in Snowshoeing
- 5 in Snowmobiling
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Global Ranking
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Hiking SAC ScaleT2 Mountain Hiking
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Trail TypeSingletrack
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Bike TypeAM, XC, Fat
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DirectionBoth Directions
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Climb DifficultyBlue
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Physical RatingModerate
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Trail VisibilityAlways easy to follow
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SeasonJuly-October
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Family FriendlyYes
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Dogs AllowedYes
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eBike Allowed
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Land OwnerUSFS
The high elevation and thick timber make this trail one of the last in the region to shed snow, and drifts are common into late June. The trail to Cottonwood Lake is very popular with backcountry horsemen and horsewomen, so be alert, and make sure to park courteously, leaving room for horse trailers to turn around.
The trail to Cottonwood Lake is a moderate climb. From the lake, the trail climbs steeply to the top of Thunderbolt Mountain via the L.O. Connection. The junction is at the north end of the lake; if you carry on farther than that you have missed it and are headed into the Little Blackfoot watershed.
Access Info
Take the Bernice exit of I-90 (Exit 151) and follow the Boulder River Road (staying to the left). Stay on the Boulder River road to the Thunderbolt Creek road, which is directly opposite the Whitehouse Campground. The junction is a distinctive Y and is signed. The Thunderbolt Creek road ends at the trailhead.
Trail Supporters
USFSLand Manager
Local Trail Association
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-
Please consider joining or donating to the local trail association to supportDonate to earn trail karma!
trail development & maintenance.
Traditionally Indigenous Territory
Recent Activity on Trail
Past Week
- 0 rides
6 Months
- 0 rides
All
- 11 rides
- Last: Nov 9, 2025
| c1 | c2 | c3 | c4 |
|---|---|---|---|
January | February | March | April |
May | June | July | August |
September | October | November | December |
Thunderbolt... Trail Reports
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Trail Conditions
- Unknown
- Snow Groomed
- Snow Packed
- Snow Covered
- Snow Cover Partial
- Freeze/thaw Cycle
- Icy
- Prevalent Mud
- Wet
- Variable
- Ideal
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The colour categories are based on what percentage of riders are riding a trail in its intended direction.
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Directions to thunderbolt-mountain-trail trailhead
(46.283170, -112.473850)
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Routes with this trail
★ 3.0 • 13 miles • 2,249 ft • 3 • Out & Back •
The top of Thunderbolt Mountain offers one of the most outstanding 360-degree views in the Helena area....
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Nearby Trails
- Sno-7002 4 miles
- Thunderbolt Mountain Summit 4 miles
- L.o. Connection 5 miles
- Cdt Connector 5 miles
- Sno-7007 5 miles
- By evasive
MBG & contributors - #30743 - 3,750 views
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Frequently Asked Questions About Thunderbolt Mountain Trail
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Where is Thunderbolt Mountain Trail located?
Thunderbolt Mountain Trail is located in Little Blackfoot, Elliston, Montana, United States. It is part of the Little Blackfoot trail network. The trailhead is located at coordinates 46.28317, -112.47385.
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How hard is Thunderbolt Mountain Trail?
Thunderbolt Mountain Trail is rated as Blue difficulty. The physical rating is Moderate. The average grade is 4.5%. The climb difficulty is rated Blue.
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What is the elevation gain for Thunderbolt Mountain Trail?
Thunderbolt Mountain Trail has 1,060 ft of elevation gain. The trail has 31 ft of elevation descent. The elevation ranges from 6,396 ft to 7,425 ft.
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Is Thunderbolt Mountain Trail a point to point trail?
Thunderbolt Mountain Trail is not a point to point trail. The direction is Both Directions. The trail type is singletrack.
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