Big Sky North (Snowmo)
Big Sky North (Snowmo) Trail is a 65.5-mile snow trail in Custer Gallatin National Forest, Montana. The Forest Service rates it trail class 2 to 4, moderately developed to highly developed. It is open to snowmobile, snowshoeing and cross-country skiing.
Trail conditions, closures and hazards are not tracked here. The Custer Gallatin 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 | 45.5309° N, 111.1354° W · Directions ↗ |
| Other end | 45.1015° N, 111.2190° W · 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 6 segments.
The trail
| Length | 65.5 miles |
| Trail class | 2, moderately developed; 4, highly developed |
| Type | snow trail |
| Surface | native material |
| Typical grade | 12-20 percent |
| Typical tread width | 18-24 inches |
| Motor vehicles | Open to at least one motorized use |
| Accessibility | Not evaluated |
| National designation | National Recreation Trail or other national designation |
| Trail numbers | 900 |
| Forest | Custer Gallatin National Forest (unit 0111) |
| 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.
Weather by month
Allowed uses
| Snowmobile | Allowed 12/02 to 04/15 (month/day) |
| Snowshoeing | Allowed year-round |
| Cross-country skiing | Allowed year-round |
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.
Trailheads
Buffalo Horn Trailhead No season published | under 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.
Trails nearby
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
- PrescribedFy26 West Zone Piles Unit 22N 999C 999D Rx
14 mi from the trail midpoint
Distance is to the reported incident point, not the fire edge. Closure orders are on the forest's official page.
Explore
Historic places nearby
Guidebooks for Montana
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Titles come from Open Library's catalog, matched by subject heading or by title.
Reference
Questions people ask
How long is the Big Sky North (Snowmo) Trail?
The Forest Service records 65.5 miles under this name in Custer Gallatin National Forest, the sum of 6 segments.
Source: Forest Service trail layer
What is allowed on the Big Sky North (Snowmo) Trail?
Snowmobile, snowshoeing and cross-country skiing are allowed. The trail is open to at least one motorized use. Some uses are seasonal. The allowed uses section lists the dates.
Source: Forest Service trail layer
Where does the Big Sky North (Snowmo) Trail start?
The line begins at 45.5309° N, 111.1354° W and ends at 45.1015° N, 111.2190° W. The nearest recorded trailhead is Buffalo Horn Trailhead, under 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 Sky North (Snowmo) Trail in a wilderness area?
No. The trail line does not cross any polygon in the National Wilderness Preservation System layer.
Source: Wilderness Connect
Where can I camp near the Big Sky North (Snowmo) Trail?
Spire Rock Campground (0.5 mi), Spire Rock Group Campground (0.5 mi) and Spire Rock Campground (1.1 mi) are within five miles of the trail. The camping section lists all 8 with site counts and booking links.
How developed is the Big Sky North (Snowmo) Trail?
Trail class 2 to 4, which the Forest Service describes as moderately developed to highly 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 Sky North (Snowmo) Trail?
The typical grade is 12-20 percent. The typical tread is 18-24 inches wide.
Source: Forest Service trail layer
Is the Big Sky North (Snowmo) Trail a national trail?
Yes. The record marks it as a National Recreation Trail.
Source: Forest Service trail layer
Who manages the Big Sky North (Snowmo) Trail?
Custer Gallatin National Forest, Forest Service unit 0111. The trail is in Montana.
Is there a fire near the Big Sky North (Snowmo) Trail?
The interagency feed shows 1 active incident within 50 miles of the trail midpoint as of 2026-11-01, the nearest Fy26 West Zone Piles Unit 22N 999C 999D Rx at 14 miles. Check the forest's closure orders before you go.
Source: Fire nearby
Source
This page is built from 6 segments named Big Sky North (Snowmo) in the Forest Service TrailNFS_Publish layer, administrative unit 0111. 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 November 1, 2026. The methodology page explains how segments become trails.