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Mammoth Crest - Duck Pass Loop



13.2 mile 21.2 kilometer point to point
82% Runnable


Ascent: 2,875' 876 m
Descent: -2,890' -881 m
High: 11,185' 3,409 m
Low: 9,026' 2,751 m


Avg Grade: 8% (5°)
Max Grade: 51% (27°)


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Trail shared by Tilman Giese

This route takes you to stunning views across the Sierra Nevada interspersed with beautiful lakes.

Tilman Giese

Features Lake · River/Creek · Swimming · Views · Wildflowers


This run will lead you up the Mammoth Crest mountain ridge to offer superb views of the Eastern Sierra Nevada and explore some of the most beautiful lakes in John Muir Wilderness and Inyo National Forest.


The trail starts at the Crystal Lake Trail, north of the parking area and steadily ascends through fir and pine forest. Once you get past the summer cabins on the left, the trail will zigzag up the northwest hillside of Lake George offering occasional views of Crystal Crag and Lake George. After a mile, you'll reach the junction to Crystal Lake Trail. Make a sharp right turn to stay on this trail.

The further up you go, the better the views will be. At a sandy switchback towards the south, you have a stunning view of the entire Mammoth Lakes basin, including Mammoth Mountain, Horseshoe Lake, Lake Mamie, and Twin Lakes. Trees are sparser beyond this point.

At two miles, you finally reach Mammoth Crest. The trail turns left, but continuing straight onto Mammoth Crest Alternate Spur is highly recommended to get spectacular views of Mount Ritter, Banner Peak, and the Minarets. Continue south over what looks like volcanic slag until the trail becomes sandy. Pass the sign for John Muir Wilderness and cross the desolate plateau while soaking in the views to the west and south.

You'll reach the highest point of the crest at roughly 4.5 miles. The trail will very steeply descend to Deer Lakes - three lakes surrounded by high mountain walls. This is a good place for a longer break. Continue along the middle lake and steadily ascend again. At this point, the trail becomes less defined, but is still recognizable most of the time. Once you reach the southeastern lake, do not continue further south, but stay on an easterly direction up a fairly rocky slope. Several maps show Mammoth Crest Trail heading further south and then up an extremely steep slope. That is not the trail.

At the top of the slope is another plateau covered in snow until late in the summer. Once you have crossed the plateau, another bowl opens up with Duck Lake and Pika Lake and its surrounding mountains. Descend towards the lake. The trail will become very hard to find very quickly. Head east and just cross the meadow. You may find small cairns that people have put up, but if you don't, then just continue until you reach the maintained Duck Pass Trail, which you follow north.

Duck Pass Trail leads you back to the Mammoth Lakes basin. The views from the top are absolutely stunning and worth taking a break before you head down further. The trail zigzags down quite steeply and passes Barney Lake on the right and Skelton Lake on the left before heading into somewhat thicker forest. At 10 miles, take Emerald Lake Trail to the left and continue descending to Emerald Lake. It is surrounded by lush green meadows that led to its name. The lake is typically very calm and glassy offering you a reflection of the mountains and trees. Past the lake, the trail follows Coldwater Creek.

At 10.8 miles, make a left turn onto Coldwater - Lake George Trail to cross Coldwater Creek. Carefully walk over the fallen tree trunk to get to the other side. The trail makes a wide right turn and leads through shadowy forest with the occasional green meadow and small pond, some of which offer marvelous reflections. At 12.4 miles, you'll reach Lake Barrett—a great place for taking in the scenery with Mammoth Mountain in the background, but also a great place to swim on a hot summer day. The trail briefly veers away from the lake to join TJ Lake Loop. Stay right to return to Lake Barrett.

Once you leave Lake Barrett behind you, the trail will steeply descend to Lake George and return you to Lake George Campground.

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Oct 23, 2018
Adam Hodges
Sep 30, 2018
Beckham Thomas
Great loop with amazing views. Lots of lakes. 13.3mi
Sep 8, 2018
Jason Wheat
Aug 19, 2018
Juan Vargas
Began at Crystal Lake Trail and Finished at Coldwater Campground. Had to run all the way back to Lake George. Amazing run overall 13.4mi — 3h 20m
Jul 14, 2018
Chad V 13.2mi — 4h 07m

Trail Ratings

  4.8 from 11 votes


  4.8 from 11 votes
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in California


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6,049 Since Sep 3, 2017



The Duck Pass Trail climbs up the valley from the trailhead at Coldwater Campground.
Oct 17, 2018 near Mammoth…, CA
Duck Lake and Pika Lake viewed from the top of Duck Pass.
Oct 17, 2018 near Mammoth…, CA
Deer Lakes from the eastern ridge of the surrounding mountains
Sep 16, 2017 near Mammoth…, CA
Lake George through the trees on Mammoth Crest Trail.
Sep 16, 2017 near Mammoth…, CA
Crystal Crag viewed from the Mammoth Crest Trail.
Oct 23, 2018 near Mammoth…, CA
Crystal Crag viewed from the Mammoth Crest Trail.
Oct 23, 2018 near Mammoth…, CA


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