Marinwood, CA, United States · Saturday, March 20, 2027
Fixed Distance 100K
The Big Alta
185 days away
100 km Distance
not publishedn/a Climbing
5.0 est Grit · Challenging
Calculated from 100 km alone — the organiser has not published an elevation profile. Read 5.0 as a floor, not a verdict.
What the course asks
Field size ~196 Mid-sized. Company early, well spread out by halfway.
DUV results for the 2026 edition (50km) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.
Typical conditions, March
Daytime high 15°C
Night low 7°C
Rainfall Mostly dry
Daylight 12 h 06 m of light
Regional 2001-2020 average for March — NASA POWER, grid elevation 87 m. Not a forecast.
The Aid Station
Course-specific beta from the community
With trail terrain, choose a shoe with moderate cushioning for optimal performance.
For 100km+ efforts, prioritize real food at aid stations to prevent palate fatigue.
Gear for this race
Chosen for 100 km of trail.
- Trail Running Shoes100 km of trail — cushioning that is still there in the last quarter.
- Race NutritionPast 100 km the palate quits before the legs do — carry more than one flavour.
- Hydration VestsFlask capacity for 100 km, without the bounce.
- Headlamps100 km almost certainly means running into the night.
- AccessoriesChafe and blisters end more 100 km races than fitness does.
Similar races
Other 100K trail ultras, closest in distance first.