East Portal Bike Climb - PJAMM Cycling

3.3 mi
2,001 ft
11.4 %


Page Contributor(s): Bruce Hamilton/Stacy Topping


"East Portal is a very steep and dramatic climb up from the Gunnison River within Black Canyon of the Gunnison National Park in western Colorado. In fact it is one of the steepest and most difficult ascents in the United States. It has an isolated and unusual start (besides being in a national park) in that you have to descend the hill (challenging) before you can climb it. Enjoy the river and the deep canyon (ride along it within the soaring black granite walls to the dam before you head out) and the pastoral setting at climb start as you may be focusing primarily on your pain level much of the way up and out." (This quote is presented with the approval of John Summerson, from his book, The Complete Guide to Climbing (by Bike) in Colorado, pg. 130.)
The good news:  175 yards at 1.1% beginning at mile 1.4.  The bad news:  The rest of the climb.  This brief but epic bike climb averages 11.4% for 3.3 miles.  31% of the climb (one mile) is at 5-10%, 47% (1.6 miles) is 10-15%, and 14% (one-half mile) is in the 15-20% gradient range. The steepest quarter-mile is 17.1% and there is a continuous mile averaging 14%.  

Consult the PJAMM "Full Forecast" feature for the time you expect to arrive at the finish to assess what clothing to bring on your ride.
Roadway:  Excellent condition.

Traffic:  Negligible. 

Parking:  This is an odd one - to get to the start of the climb, you ride down 3.5 miles into a dead end canyon to the start of the climb.  On our two trips to East Portal, we parked at the top of the climb and rode our bikes down to the start - that's tough because the entire time you are riding down you'll stress that you will have to ride back up this monster!
Provisions:  None.

Bike:  For all you normal cyclists out there - compact chainring and at least a 32t cog on the back. 
Before heading out on any cycling adventure check out our Things to Bring on a Cycling Trip and use our interactive check list to ensure you don't forget anything.
This one is a bit out of the way.  The closest place to stay is Montrose about 10 miles away.  In addition to hotel options, the Montrose area has some highly rated house rental options as well.



Difficulty: Strenuous



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Jun 3, 2021
East Portal closed for construction until 2022
Apr 5, 2021
difficulty: Strenuous
scenery: 4
traffic: 5
road: 2
Apr 5, 2021
scenery: 4
traffic: 5
road: 2
A brute of a climb, the steepest in CO. Check your brakes before the descent as it is challenging. Little traffic will allow you to concentrate on the double digit grade present almost all the way back out. Must do.

Climb Profile Not Found

Cycling East Portal, Colorado - bike parked in front of Black Canyon of the Gunnison National Park

Cycling East Portal

Ride 3.3 miles gaining 2,001’ (0 descent) at 11.4% average grade.

Black Canyon of Gunnison National Park, Colorado -- Established 1999, 30,750 acres.

Cycling East Portal, Colorado - panoramic view of flat mountaintops with large valley between them

This one is a bit of an outlier, but well worth the drive to get to Black Canyon! The climb itself is brief, but similar to Mt. Ascutney in Vermont, gives you as much pop in three miles as you will get on any of the Top U.S. 100 Climbs. The Colorado climb is incredibly steep and gives you spectacular views of the surrounding mountains and vegetation.

Cycling East Portal, Colorado - photo collage, PJAMM Cycling logo in corner, PJAMM white SAG van parked next to NPS sign for Black Canyon of the Gunnison Nationla Park, aerial views of road snaking up hillside, bike parked in front of signs for 16% grade and "Use low gear" sign, bike parked against white fence with PJAMM cycling jersey draped over it

We start the climb at the bottom of an extremely steep canyon along the Gunnison River.

Cycling East Portal, Colorado - cyclist wearing PJAMM Cycling jersey parked on roadside next to creek surrounded by grey rocky hillsides

Cycling East Portal, Colorado - photo collage, PJAMM Cycling logo in corner, signs for Gunnison Tunnel and Diversion Dam, bike parked next to sign, sign for National Historic Civil Engineering Landmark

Cycling East Portal, Colorado - informational signs, photo collage, PJAMM Cycling logo in corner

On a climb this steep there are bound to be hairpins, and this one does not disappoint with 13 compressed into this 3.2 mile monster.

Cycling East Portal, Colorado - aerial views of road snaking through hillsides, PJAMM cycling logo in corner

Cycling East Portal, Colorado - photo collage, PJAMM Cycling logo in corner, cyclist climbing on one-lane, rural roadway surrounded by dirt and scrub brush

The views are spectacular and the climb quite challenging (on the ascent, however, you’ll have your back to the views and likely have your head down and grinding it out!). The National Park Service describes the area "Deep, Steep and Narrow: Big enough to be overwhelming, still intimate enough to feel the pulse of time, Black Canyon of the Gunnison exposes you to some of the steepest cliffs, oldest and craggy spires in North America. With two million years to work, the Gunnison River, along with the forces of weathering, has sculpted this vertical wilderness of rock, water, and sky."

Cycling East Portal, Colorado - photo collage, PJAMM Cycling logo in corner, views along the climb

Bicycle ride up East Portal - road far below

View from the top.

Steepest quarter mile (well, it’s ALL steep!) begins at mile 1.1 (16.6%) and mile at 0.4 (13.7%).

Consider camping at the East Portal Campground, which looked like a great place to camp and gets high ratings on Yelp.  Since you are travelling to one of the more remote of the Top 100 climbs, making a day or weekend of it in this amazing National Park and canyon area is worth the while.

Roadway Surface and Traffic Report:  Roadway is in excellent shape and there is minima and slow moving traffic on the way up.

You will get a very good sense of the climb and surroundings by viewing our YouTube videos
here and here. ​