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Flattop Mountain Trail



4.2 mile 6.8 kilometer point to point
69% Runnable


Ascent: 2,533' 772 m
Descent: -183' -56 m
High: 12,295' 3,747 m
Low: 9,762' 2,975 m


Avg Grade: 12% (7°)
Max Grade: 42% (23°)


No Dogs
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Trail shared by Trail Master

Popular trail reaching the long saddle on the Continental Divide between Hallett Pk. & Ptarmigan Pt.

Trail Master

Features Views · Wildflowers · Wildlife

Runner Notes

Snowfields and lots of loose rocks.


To reach the Flattop Mountain Trail, first ascend above Bear Lake heading north through young aspen to where the-the Bear Lake TH to Fern Lake TH trail splits from the Bear Lake - Mill Creek Trail. From here, the Flattop Mountain Trail itself begins, leaving to the west along a ridgeline. Soon the Fern - Odessa Lake Trail branches off to the right (northwest) but instead, continue left on the Flattop Mountain Trail, switchbacking steeply uphill. Surmount the forested eastern flank of Flattop pausing for views of Dream Lake, Longs Peak, Emerald Lake and Tyndall Glacier. Tyndall is one of only five active glaciers in the Park and is responsible for carving the valley below.

After treeline, the grades moderate and the switchbacks end. Follow the well-defined path into open tundra, using cairns for guidance over snowfields. The trail reaches a hitching post affording good views of Hallett Peak across the gorge. Next, scale a permanent snowfield and cover level ground on the final approach up to Flattop Mountain. No sign marks the summit, but the Flattop Mountain Trail - Tonohutu Creek Trail junction is generally recognized as your final destination.

This wide flat saddle along the Continental Divide offers a rare opportunity to explore the tundra. See if you can identify landmarks such as Hallett Peak, Otis Peak, Taylor Peak, Longs Peak, Notchtop Mountain, Ptarmigan Point and portions of the Mummy Range, Never Summer Range and Grand Lake.

Note: Bear Lake is a heavily used trailhead with limited parking. Arrive early to get a spot. About half of this trail goes above treeline and is very exposed. Expect strong sun, wind, cool temperatures, and rapidly changing weather conditions. Get an early start to avoid afternoon thunderstorms.

Flora & Fauna

Pika, ptarmigan, elk, bighorn sheep and mountain goat. Spruce, fir, wildflowers.

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Aug 20, 2018
Andrew Sharpe

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Trail Ratings

  4.5 from 35 votes


in Bear Lake


  4.5 from 35 votes
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in Bear Lake


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41 Views Last Month
7,362 Since Jul 15, 2015



View of Glacier Gorge and Longs Peak from the trail
Apr 22, 2019 near Estes Park, CO
Ground squirrel in Rocky Mountain National Park
Jan 19, 2015 near Estes Park, CO
Flattop Mountain Trail with Longs Peak in the distance.
Sep 13, 2019 near Estes Park, CO
Alpine Meadows on Flattop Mountain Trail
Aug 3, 2017 near Grand Lake, CO
Emerald Lake from Flattop Mountain trail in Rocky Mountain National Park
Jul 15, 2015 near Estes Park, CO
Hallet Peak  from the Flattop trail
Aug 6, 2019 near Grand Lake, CO


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