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Thunder Mountain

Located in Red Canyon just outside Bryce Canyon National Park, Thunder Mountain combines technical riding with amazing views. The trail is 7.9 miles long and is both technically and physically difficult. It's one of Utah's classic must-ride trails.

The Thunder Mountain trail climbs past hoodoos of limestone. Original trail review and photos by Bruce on July 17, 2001. Latest update 2021.

The top elevation on the Thunder Mountain trail is 8200 feet, so "spring riding time" comes late here. The expected riding season will be late May through October.

The Claron Formation limestone is the same rock that's found in beautiful Bryce Canyon National Park. The scenery is the reason riders come here.

Before tackling Thunder Mountain, you should be comfortable riding on loose surfaces, near steep drops, and through tight switchbacks. That means expert riders. Strong and determined intermediates can manage with a bit of walking.

Much of the trail is "climb a little then drop back down a little" over and over. You'll never do so much climbing on a "downhill trail."


The lower Thunder Mountain trailhead is on Highway 12 at 7100 feet elevation, 3 miles from US 89. The trailhead is on the right side of the road just as you enter Red Canyon. This is where you'll go first, whether to leave a shuttle vehicle or to begin your ride up the paved bike trail. (I intend to talk you out of doing the out-and-back ride. But if that's what you're doing, the trail entry to start uphill is at the rear right corner.)

Exit from the trail at the lower Thunder Mountain trailhead -- or entry to the trail if you're riding uphill.

The upper trailhead is at Coyote Hollow. As you drive east on U-12, go 8 miles up Red Canyon until the road levels out in a sagebrush area. A gravel road, called "Fremont ATV Trail" crosses U-12 and you'll see a bathroom and parking area to your right. The sign says "Red Canyon Trail" -- meaning the paved trail -- but the road goes to Coyote Hollow and the top of Thunder Mountain. Turn right but don't park here. Drive 2.1 miles to the Coyote Hollow trailhead for your shuttle drop-off.

This is the Coyote Hollow trailhead, and the end of the road. Don't be fooled by the big kiosk about half-way down the Fremont ATV trail.

Riding options!

Almost everyone does this trail top-to-bottom, whether by shuttle or with a climb up the paved Red Canyon trail. It IS possible to ride it from the bottom out-and-back. I did that 20 years ago, and it was brutally hard. And now, as the trail has been affected by increased horse and bike traffic, the switchbacks in miles 1.5 to 3 are almost impossible to clean uphill because of the combination of boulders and moon dust.

About to have some serious fun! Looks pretty easy so far, right?

Out-and-back is a brutal proposition, because it's easy to underestimate the beating your legs will take from the up-and-down riding. If you ride the trail as an out-and-back, it's 15.8 miles, and you'll do over 3500 vertical. This is a trail that, in a very real sense, is "uphill both ways."

Typical trail section for the first 4 miles. Up and around, then back down.

So I'm going to gently suggest that, if you have two cars, you do the shuttle thing. If not, plan on a loop ride where you enjoy the 5.4 mile cruise up the paved Red Canyon trail, the 2.2 miles on gravel road that is the Fremont ATV trail, then 7.9 miles of fun on Thunder Mountain. Your ride will be 14.5 miles total, with total climbing of 2200 vertical feet. Only 900 feet of that climbing will be on paved trail and gravel road.

View back to the east from a high spot in the trail. Not THE high spot, just A high spot.

But here's another option. You can backtrack a bit down U-12 and take the gravel road to Casto Canyon. After climbing Casto, hang a right turn on Fremont ATV and ride south to the trailhead, crossing Highway 12 as you go. The miles are mid-20s with around 300 feet more climbing than the paved bike trail. Casto is an easy ride technically.

Hoodoos in the canyon near the end of the downhill ride. Serious eye candy here!

About the ride!

The dirt and rock are from the Claron Formation. This soft rock originated at the bottom of a large lake that extended from eastern Utah into the Bryce Canyon area. It was deposited about 40 million years ago, long after the extinction of the dinosaurs. Mostly it's creamsicle orange, with some bands of white.

Melted creamsicle terrain as we get started on Thunder Mountain.

Riding through the forests of the Thunder Mountain Trail will seem strange to bikers who are used to the dense brush and trees of the high Wasatch. Here, long-leaf pines stand well-apart, with low manzanita scrub on exposed rocky soil, and a few cedars sneaking in between the pines.

Manzanita is a handsome spreading shrub with round, firm light-green leaves growing on dark red branches.

The singletrack undulates up and down, back and forth. If your legs are fresh, you may consider this a cruise. But most riders will find this ride a satisfying bit of work. As you look at the map below, understand that every tiny wiggle is a descent into -- and a climb out of -- a drainage. You're never "finished" with the climbing until the last mile.

Near the Coyote Hollow trailhead, the trail rolls up, down, and around mounds of orange and white rocky soil.


It's rare to encounter hikers on the trail, but Thunder Mountain is used daily by commercial horse outfitters. The typical equestrian group is 6 to 10 riders, and they'll be together in a line. You may need to backtrack a bit on the trail to find a spot where you can safely get off to the side to let the horses past.

The first half of the trail has few breakout views. This is one of them, looking north.

When riding top to bottom, the first 4 miles are intermediate trail. You'll climb a bit then descend a short distance as the trail contours the hillside. But the general trend is to slowly gain elevation. You'll go from 7900 feet at Coyote Hollow to 8200 at the ride's high point.

A selfie with the hoodoos is a must-do for this ride; in fact I think it might be legally required!
There will be several "false summits" where you think you've crossed the top and now be going mostly downhill. Sucker! You're about to climb again! You're only on the downhill side when you can see the long stretches of the trail descending into the deep canyon to your right.

Looking from a ridgeline to downhill switchbacks ahead. Now you're really on the way downhill now!

As the trail begins dropping quickly just after mile 4.5, there will be some rough steeps and very difficult switchback turns. The embedded boulders are more difficult because of the deep dust in the trail.

Steep pitch down to a difficult switchback.

But at least you're through climbing, right? Ha! The trail just keeps finding new excuses to climb back uphill. After all, you picked a trail that climbs 1200 vertical feet as it goes downhill!

Climbing again! But just look at these views!

Take some time to enjoy the two exposed fins where the world falls away on both sides. This is a favorite photo and video spot!

Dominic, Matt, and Mike thread along the top of the ridgeline fin. Headed downhill, we'll be dropping off this fin towards the rocks in the background via a series of sharp switchbacks into Red Rock Canyon. Photo September 2003.

As winter run-off, rain and erosion change the trail, you may find it a different experience. For example, this photo spot now has a steep rock garden instead of smooth dirt. And when the trail is firm -- instead of deep horse- and bike-churned moon dust -- it's a very different ride!

Bruce attacks a short steep on lower Thunder Mountain in 2003.

Another series of switchbacks is coming, this time closer together with tighter turns. You're now dropping the steep flank of the deep colorful canyon you've been seeing for the last couple of miles. You're going to lose 100 vertical feet in 1/10th mile, an average 20% down-slope!

On the final run of switchbacks.

The trail now drops to the canyon bottom. Did you take a minute or two to enjoy the fabulous views of orange rock and hoodoos?

We're about to hit the dry creekbed and cross over.

The trail hits a trail fork at the bottom of the canyon. Turn to the right and climb over a low rise. Yes, climb. What made you think you were through climbing?

The trail now rockets north toward the trailhead for one mile. It's the only section of non-interrupted downhill you get on this ride! Watch for horses, hikers, and climbers!

Heading toward the trailhead on the final mile. A great ride. Well-done!

Bottom Line!

Thunder Mountain is a classic, and it's one of Utah's Must Ride trails. The scenery is awesome and it's something you'll never forget. But it's not a cushy ride, and certainly not for inexperienced or weak riders. It's just as hard with a shuttle as it is if you do the loop ride. You can ride it as a "scenic loop," as a butt-kicking "downhill," or as a seriously insane hill climb out-and-back.

Jackie pauses on the ridgeline, as we head towards the top of Thunder Mountain on a very tough out-and-back ride on July 17, 2001.

 Thunder Mountain: a video from the Good Old Days of 2003

 If the above video does not appear on your browser/device, you can watch it on YouTube by clicking here.

Getting there:

Coyote Hollow Trailhead:  Driving east on U-12, go all the way up Red Canyon until the road levels out in a steppe area at the top (about 8 miles from US-89). Watch for a gravel road GPS N 37 43.169' W 112 15.322' (on both the right and left sides of the road) about 1/2 mile after reaching the top of the hill. The road is labeled "Fremont ATV Trail." Turn right and drive 2.1 miles to the Coyote Hollow trailhead at GPS N 37 42.156' W 112 16.758'.

Thunder Mountain Trailhead: Drive east from US-89 on U-12 (about 3 miles) until you reach the Thunder Mountain parking area on your right, just before "Red Canyon" sign. GPS is N 37 44.595' W 112 19.747'.

Riding resources for this trail:
One-page guide to this trail
GPS track file (right-click and "Save as..."):
     GPX loop ride    Multi-track file
Topo maps for printing:    High-Res
Lodging, camping, and shops:    Link to Red Canyon area resources

Copyright 2003 Mad Scientist Software Inc
updated 2021