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Mammoth Trail Fest Mammoth Lakes, California, United States

Name: Mammoth Trail Fest
Start: 2026-09-25
End: 2026-09-25

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Mammoth Trail Fest

Course maps

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Route source

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Dragon Ascent
Tenkay
26k
50k

Foot race | 25 Sep 2026

31.4 mi

Distance

Elevation gain

11,024 ft

Elevation high

9,049 ft

Elevation avg

Trail/Dirt

Elevation loss

8,045 ft

Elevation low

21%

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 21% over 31.4 mi, which means that the energy expenditure for the run is equivalent to running a flat 38.0 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 20 Jun 2026

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 2026.

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Stats summary

Race distance	Distance	Ele gain	Ele loss	Ele avg	Paved	Gravel	Dirt	Narrow
Dragon Ascent	3.0 mi	2,467 ft	33 ft	9,751 ft	6%	94%	0%	86%
Tenkay	6.1 mi	722 ft	722 ft	8,396 ft	1%	51%	49%	99%
26k	16.2 mi	3,629 ft	3,622 ft	9,121 ft	19%	63%	18%	78%
50k	31.4 mi	6,145 ft	6,142 ft	9,049 ft	16%	70%	14%	80%