DateExpected
Early September 2027
Based on past editions. We'll confirm when the organiser announces.
Venue
Mammoth Bar OHV Area, Old Foresthill Rd, Auburn, CA 95603
Auburn, Placer County
Countdown
September
A point-to-point half marathon with 1,311 m of climbing, so expect real hills rather than a gentle jog. Small field, and you run from one place to another.
Key facts
01Cut-off at 12:00, four hours after the start
02Aid stations at miles 2, 5 and 11.3
03Point-to-point course, so plan your travel back to the start
Create a free training plan for the Mammoth Bar Trail Runs 21 km
7-day free trial, no card required
The course
The route
Auburn
Distance21km
Total climb1,311m
StartElevation
0 kmDrag map to rotate20.7 km
Weather
Early-September, Auburn
35°CTypical high
17°CTypical low
11°CColdest in 20 years
2%Days with rain
Highs around 35°C and lows around 17°C, but it has dropped to 11°C. Rain on 2% of days.
NASA POWER data, 2006-2025, the week either side of race day
2025 results
Who finishes, and how
#RiderTimeAvg speed
01Jessy Herring02:56:117.2 km/h
02Emily Sall03:01:547.0 km/h
03Ramona Marshall03:29:136.0 km/h
9
Women finishers
4:10:27
Median time
5.1 km/h
Median speed
Women · 2025 results, as published by the organiser.
How fast could you finish?
Get a prediction based on your recent training
Organiser
Training
Training for the Mammoth Bar Trail Runs 21 km
We don't do generic plans. We combine deep knowledge of this race's demands with your recent training, then build a plan with you that progresses as you do.
Beina integrates directly with your existing tools to understand your current fitness, and synchronise your planned sessions.
Intervals.icuWhat a Mammoth Bar Trail Runs 21 km plan targets
Typical sessions
21 km with 1,311 m of climbing
Time on feet and fatigue resistance
Fuelling and pacing for the whole event
What your weeks look like
Typical sessions
Long runs that build time on your feet
Tempo and threshold sessions to hold race pace
Back-to-back weekend runs for fatigue resistance
Not a generic schedule
Typical sessions
Built from your current fitness and the time you actually have
Adapts every week as Beina learns how you respond
Syncs your sessions straight to Garmin and Wahoo
One clear next session, never a wall of spreadsheet
Entries open now
Get your Mammoth Bar Trail Runs 21 km plan.
7-day free trial, no card required.
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