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Mammoth Trail Fest Mammoth Lakes, California, United States

Name: Mammoth Trail Fest
Start: 2025-09-18
End: 2025-09-21

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Mammoth Trail Fest

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Dragon's Back Ascent
26k
50k

Foot race | 20 Sep 2025 | 7:30 am

31.4 mi

Distance

Elevation gain

11,020 ft

Elevation high

9,078 ft

Elevation avg

Trail/Dirt

Elevation loss

8,054 ft

Elevation low

25%

Climb factor

What is climb factor?

The climb factor for a course is the percentage of your energy used in hill-climbing compared to the energy expended running the flats.

This course has a climb factor of 25% over 31.4 mi, which means that the energy expenditure for the run is equivalent to running a flat 39.1 mi.

Climb factor is provided courtesy of Ben Crowell, who both authored climb factor's scientific paper and wrote the open source software for it. You can read more about it here .

Course last updated 6 Nov 2022

All values approximate

Distance & elevation data

The distance or elevation data not precisely what you expect for this route?

Data from a GPS device can be rough, especially in areas where the terrain (trees, canyons) interfere with GPS signals. And routes drawn on our maps are reliant on people marking trails from satellite images -- the details of which can be hidden by trees.

Elevation can be tricky too. Elevation data is stored on spaced topographical lines, and determining the elevation of a point requires computers to estimate based on how close the point is to the topographical line.

We mitigate this by calculating distance in 3-D (think Pythagorean theorem) and using mathematical techiniques to smooth the elevation data. We come close, but no one can be perfect with imperfect data, even in 2024.

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Surface detail information for this course is unavailable.Learn more.

Surface detail information

HelloDrifter takes a few minutes to obtain surface detail information for every course created on the site. When present, clicking the "information" icon on the right of the map will cause sections of the course to display whether they are path, road, gravel, or dirt.

Please note that this feature is not available everywhere in the world (yet). We currenly support North America, Australia, and Europe. Even then, surface details aren't available unless the course matches data that is available in OpenStreetMap. (Typically, this means that we can't get surface details for very remote courses or courses with imprecise GPX data.)

If you have any questions, contact us through the link at the bottom of the page.