PTarmigan Tunnel Road — Many Glacier to Belly River via Swiftcurrent Ridge
Glacier's forgotten back door into Belly River.
Most people in Glacier National Park never leave the pavement. The Ptarmigan Tunnel Road corridor — running northeast from the Many Glacier valley floor toward the Belly River drainage via the Chief Mountain border country — is for the ones who do. Starting off the Chief Mountain Highway spur near Babb, Montana, this raw dirt and gravel route threads through Blackfeet Nation boundary country before dropping into one of the park’s most isolated drainages. The Belly River itself is a landmark: cold, clear, and crossed at a low-water ford that stops stock vehicles cold when runoff is running. Grizzly bear activity here is not hypothetical.
This is high-clearance 4WD territory, full stop. The ford alone requires at minimum a lifted truck with 33-inch tires and some patience — scout it on foot before you commit. Dispersed camping inside park boundaries requires a backcountry permit from Glacier’s permit office in Apgar or St. Mary; plan ahead because quotas fill fast. Best window is mid-July through mid-September before the ford levels drop and the grizzlies move to lower elevations. Cell service is zero once you leave Babb. Fuel in St. Mary, water from the river treated. What you get: a Glacier experience that 99% of park visitors never see.
Trail Specs
| Difficulty | Difficult |
|---|---|
| Trail Type | Backcountry, Technical 4x4 |
| Surface | Dirt, Gravel |
| Features | Camping, Historic, Remote, Scenic, Water Crossings |
| Length (miles) | 18 mi / 29 km |
| Duration | 1-2 days |
| Max elevation (ft) | 5200 ft |
| Best season | Mid-July to Mid-September |
| Minimum vehicle | Lifted 4WD high-clearance with snorkel recommended |
| Nearest town | Babb, Montana |
| Land manager | Glacier National Park / Blackfeet Nation |
| Permit required | Yes |
| Cell service | None |
| Water crossings | Yes |
| Dispersed camping | Yes |
| Official sources | nps.gov |
| Start coordinates | |
| End coordinates | |
| Copy both for Google Maps directionsClick to copy the directions URL · or open it directly in a new tab | |
| Find on Google | Search on Google → |
Location
Trail Conditions
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Frequently asked questions
Can a stock Tacoma or 4Runner run this trail, or do I need a built rig?
A stock Tacoma or 4Runner will likely get hung up — this trail demands genuine high clearance, a locker or aggressive traction, and a snorkel is strongly recommended due to water crossings with unpredictable depth. A lifted, skid-plated rig is the minimum you want here. Don't push your luck on trail this remote.
When does this trail actually open, and can snow close it mid-summer?
Mid-July to mid-September is the reliable window, but Swiftcurrent Ridge holds snow well into summer and the access road can be impassable into late July after heavy winters. Always check current conditions with Glacier NP before you roll — don't assume the calendar means the road is clear.
Do I need a permit to drive this, and does the Blackfeet Nation land require anything separate?
Yes — Glacier National Park requires a backcountry permit for overnight use, and the Belly River corridor sits adjacent to Blackfeet Nation land, so verify current land access agreements before your trip. Contact the park directly at nps.gov/glac and confirm tribal access requirements with the Blackfeet Nation if your route crosses reservation boundaries.
What's the hardest section of the trail and what makes it technical?
The descent off Swiftcurrent Ridge toward the Belly River valley is the crux — steep, loose, and narrow with exposure and no room for error. Combined with water crossings at the bottom that vary in depth depending on snowmelt, this section has stopped plenty of capable rigs. Approach it slow, walk crossings before you drive them.
How far is the nearest gas from the trailhead, and is there any cell service on the route?
Babb, Montana is your last real fuel stop — roughly 10 miles from the Many Glacier trailhead — and it's a small outpost, so top off before you head in. There is zero cell service on this entire 18-mile route, and that's not an exaggeration. Carry a satellite communicator; this is not the trail to skip that gear.
Trail track
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