Portal to Porcupine Details

Activities
- Mountain Bike
- Hike
- Trail Running
- Dirtbike/Moto
Riding Area

Southern Gallatin Range
Big Sky, Montana
Difficulty Rating

Black Diamond rate
Trail Type

Singletrack
Direction

Downhill Primary
Popular direction shown
Climb Difficulty

Double Black Diamond
Physical Rating

Hard
Trail Visibility

Always easy to follow
Dogs Allowed

Yes
Global Ranking

#51413 in Mountain Biking
Local Popularity
65 in Mountain Biking [+]
- 5 in Trail Running
- 5 in Hiking
- 5 in Dirtbiking

One of the old school Big Sky classics usually done as a shuttle up Portal Road. A little rough due to motorcycle usage.
Starts out with a steep hour long climb; then a long, tiring, fairly technical, rocky descent with a several tight rocky switchbacks. There’s a nice viewpoint of Ramshorn Peak, Gallatin Canyon, and the Southern Madison Range about a third of the way down, let the brakes cool down. Next, watch out for the gnarly rut about 50 yards long that can be taken at speed, but maybe not. Some steep loamy sections appear near the bottom. Some folks may complain about the lack of flow, but don’t listen, this is a classic.
Shown as a “trail” here on Trailforks, it’s actually more of a “route” encompassing 3 or 4 trails and junctions, so follow the app closely. At the end, bear left/straight on Grizzly Loop, enjoy one last stinger here.
Alternatively, about a mile above the bottom, take First Creek. It’s an easy to miss right hand turn, use the map. It’s a little better built and spits you out higher up on Grizzly Loop, go right for a flowy exit, no stingers.
One last note, it can be done from the bottom, Mike B. only dabbed a couple times.

Local Trail Association

Southwest Montana Mountain Bike Association (www.southwestmontanamba.org)
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Traditionally Indigenous Territory

More Stats for Portal to Porcupine bike trail trail

Altitude change

-1,388 ft
Altitude min

6,691 ft
Altitude max

9,254 ft
Altitude start

8,079 ft
Altitude end

6,690 ft
Grade

-3.9%
Grade max

-63%
Grade min

56.6%
Distance climb

3 miles
Distance down

4 miles
Distance flat

440 ft
Avg time

03:16:03
view trail stats

status	date	description
	Jul 2, 2022 @ 10:39am Jul 2, 2022	Cleared 7 trees, there's probably another 15+ that will need a chainsaw or a lot more time to clear. The climb still has snow in some spots and is...
	Jul 31, 2021 @ 11:50am Jul 31, 2021	A few muddy puddles. Lots of creek crossings. Lots of loamy sections of trail that are riding great! Love this trail.

Portal to Porcupine

Supporters, Builders, Maintainers & Land Managers of Portal to Porcupine Trail