Big River
Big River Trail is a 43.7 miles trail in Flathead National Forest, Montana. The Forest Service rates it trail class 3, developed. It is open to hiking and horse and pack stock. It enters Great Bear Wilderness and Bob Marshall Wilderness.
Trail conditions, closures and hazards are not tracked here. The Flathead National Forest official page carries current alerts and closure orders.
Map
One end Other endLine simplified to about 100 metres. Basemap from the USGS National Map.
| One end | 48.2259, -113.5588 · Directions ↗ |
| Other end | 48.0007, -113.0506 · Directions ↗ |
The ends are the two ends of the longest connected chain of segments. The record does not say which is the usual start. The trail is recorded as 5 segments.
The trail
| Length | 43.7 miles |
| Trail class | 3, developed |
| Type | land trail |
| Surface | native material |
| Typical grade | 5-8 percent |
| Typical tread width | 18-24 inches |
| Motor vehicles | Closed to all motorized use year-round |
| Accessibility | Evaluated and does not meet accessibility guidelines |
| Trail numbers | 155 |
| Forest | Flathead National Forest (unit 0110) |
| States | Montana |
| Detail published | management level, with uses |
Values are the set across all segments. Class 1 is minimally developed and class 5 is fully developed. Grade and width are the forest's typical values, not measured extremes.
Allowed uses
| Hiking | Allowed 01/01 to 12/31 (month/day) |
| Horse and pack stock | Allowed 06/01 to 11/30 (month/day) |
A use is listed when the Forest Service records it as managed, accepted or discouraged on any segment. Discouraged still means legal. Uses marked restricted are left out. Where the forest publishes a Motor Vehicle Use Map, that map governs motorized use.
Wilderness
- Great Bear Wilderness WildernessFS · about 73% of the line is insideWilderness Connect ↗
- Bob Marshall Wilderness WildernessFS · about 24% of the line is insideWilderness Connect ↗
Inside a designated wilderness, bicycles and motor vehicles are prohibited by law regardless of the trail record, and permits or group limits may apply.
Trailheads
Open May 1 · listed none Wilderness rules and regulations apply once inside the wilderness boundary. Please refer to the BMWC information for Rules and Regulations. Solid human waste containment and fire pan/blanket use is required in the Wild and Scenic Corridor. Camping prohibited lon | 0.1 mi |
Distance is from the point to the nearest part of the trail line. Season text is what the forest wrote and is often a season name rather than a date. The recreation page link goes to the Forest Service site, which may redirect to the forest's recreation index.
Camping nearby
Campsite Atlas cards carry site counts and booking links from Recreation.gov. Forest Service cards come from the recreation layer and link the agency page.
Fire nearby
- PrescribedSb Horse Ridge Rx
15 mi from the trail midpoint
- PrescribedSb Silver Mule Rx
16 mi from the trail midpoint
- WildfireSilvertip
19 mi from the trail midpoint · 7,280 acres · 99% contained
- WildfireCamp Creek
48 mi from the trail midpoint · 9,725 acres · 99% contained
Distance is to the reported incident point, not the fire edge. Closure orders are on the forest's official page.
Explore
Reference
Questions people ask
How long is the Big River Trail?
43.7 miles, the sum of the 5 segments the Forest Service records under this name in Flathead National Forest.
Source: Forest Service trail layer
What is allowed on the Big River Trail?
hiking and horse and pack stock. The trail is closed to motor vehicles year-round. Some uses are seasonal. The allowed uses section lists the dates.
Source: Forest Service trail layer
Where does the Big River Trail start?
The line begins at 48.2259, -113.5588 and ends at 48.0007, -113.0506. The nearest recorded trailhead is Bear Creek Trailhead, 0.1 miles from the line. The record does not say which end is the usual start.
Source: Forest Service trail layer
Is the Big River Trail in a wilderness area?
Yes. It enters Great Bear Wilderness and Bob Marshall Wilderness. Wilderness rules ban bicycles and motor vehicles and often limit group size.
Source: Great Bear Wilderness Wilderness
Where can I camp near the Big River Trail?
Devil Creek Campground (4.6 mi) is within five miles of the trail. Site counts and booking links are on Campsite Atlas.
Source: Campsite Atlas
How developed is the Big River Trail?
Trail class 3, which the Forest Service describes as developed. Class 1 is a minimal, unimproved route and class 5 is fully developed, often paved.
Source: Forest Service trail layer
How steep and how wide is the Big River Trail?
The typical grade is 5-8 percent. The typical tread is 18-24 inches wide.
Source: Forest Service trail layer
Is the Big River Trail accessible?
No. The Forest Service evaluated it and found it does not meet its accessibility guidelines.
Source: Forest Service trail layer
Who manages the Big River Trail?
Flathead National Forest, Forest Service unit 0110. The trail is in Montana.
Is there a fire near the Big River Trail?
4 active incidents within 50 miles of the trail midpoint as of 2026-09-17, the nearest Sb Horse Ridge Rx at 15 miles. Check the forest's closure orders before you go.
Source: Fire nearby
Source
This page is built from 5 segments named BIG RIVER in the Forest Service TrailNFS_Publish layer, administrative unit 0110. Wilderness overlap is tested against the National Wilderness Preservation System layer from Wilderness Connect. Trailheads and Forest Service campgrounds come from the Forest Service Recreation Opportunities layer. Data refreshed September 17, 2026. The methodology page explains how segments become trails.