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High Lonesome Loop

 29 votes


15.7 Miles 25.3 Kilometers






3,242' 988 m


-3,242' -988 m



Avg Grade (4°)


Max Grade (21°)

12,046' 3,672 m


8,985' 2,739 m




Getting forecast...

A backcountry trail providing the best of high alpine running, with stunning views along the Divide.

Tiffanie Beal


Organized day-use groups are required to have a permit. Day-use permits are free. Overnight campers are required to have a permit. Campfires are prohibited.
This trail traverses between the Front Range of Colorado and the ski resort of Winter Park. If you catch good weather, you can see both sides of the Continental Divide and stunning views that go for miles.

The Hessie trailhead can be a parking nightmare. On a weekend, plan on taking a free shuttle. If you can manage a weekday run, you'll miss huge crowds. The trail is congested near the trailhead, but if you do the loop you'll often leave much of the crowd behind by the time you reach the Divide.
Features: Lake — River/Creek — Views — Waterfall — Wildflowers — Wildlife
Dogs: Leashed

Need to Know

Start your run early. The top is exposed and lighting can be a major concern. If you're out in the early season, such as June or early July, be prepared for a massive snow cornice above Devil's Thumb. You may have to route-find a bit to get around the cornice to the trail and traverse above.

Runner Notes

Prepare for high altitude, rocks, and roots.


At the Hessie Trailhead, follow the main dirt road. It is well signed and points you in the right direction. Continue as the dirt road becomes quite steep and rocky.

At mile 1.4 you'll hit a trail marker for the Devils Thumb Bypass. Take this right turn onto singletrack and continue to climb at an easier and steady grade. You'll pass through open meadows and lush scenery.

At mile 2.7, you'll continue straight on Devils Thumb Trail and start to climb a little more in earnest. The terrain will be rocky at first, but begin to even out as you reach the grassy areas of alpine lakes. Take in the scenery as you ascend and you'll be rewarded with waterfalls and wildflowers.

Take a breather as the trail levels out by Jasper Lake and then Devil's Lake. As soon as you pass the end of Devil's Lake, the climbing begins in earnest. Through thick brush and very skinny singletrack, you'll quickly gain elevation to the top of the Divide. This may require some hands-on-knees hiking as you crest over the final pitches.

Recover at the top by taking in the magnificent views. Hopefully you have good weather and a storm isn't chasing you down. The trail will continue to traverse along the Divide for roughly 3 miles.

Rounding a corner on the far side of the traverse, you'll drop into King Lake. You might even see some skiers coming down the glacier into the basin from this altitude. Start the fast descent as it quickly brings you off the divide into the meadows of King Lake.

Just after mile 10, stay right and continue on King Lake Trail. In less than half a mile, you'll once again stay right to remain on King Lake Trail. At 14.5 miles, Devil's Thumb Trail will meet up with you, and continue straight on what is now Devil's Thumb Trail. Continue to maintain your straight course all the way down to the trailhead. You'll see the Devil's Thumb Bypass Trail on your left and know that you've completed your lollipop. Take your tired legs back across the rocky and steep dirt road that you began on, and you'll find yourself back at the Hessie Trailhead and your car.

Flora & Fauna

Wildflowers cover the ground in July and August, with wildlife throughout the meadows. Catch a glimpse of the elusive ptarmigan or moose, and see plenty of marmots and chipmunks.


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Your Check-Ins


Sep 30, 2017
Justin Wright
Sep 23, 2017
Michael Reschly
Sep 18, 2017
Dave Caldwell
Awesome. Cold and windy along the ridge.
Sep 9, 2017
Ariana Schiff
Mellow hike/trot. Get an early start (before 7am) to get off the ridge line before typical afternoon storm clouds move in. 15.6mi — 5h 30m
Sep 3, 2017
Brad Dober
17mi — 5h 00m
Aug 26, 2017
Whitney Cook
Aug 19, 2017
Tom Gray
Unbelievably gorgeous run up to and across continental divide. Stunning views at every turn. A "must do" run within an hour of Denver. 22.1mi — 6h 31m
Jul 2, 2017
Jen McMurtrey

Trail Ratings

  4.8 from 29 votes


  4.8 from 29 votes
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