99.3 kmTrail🇺🇸 Calabasas, United States

Sean O'Brien 100K

Saturday, 30 January 2027In 3 months · Start 05:30

Singletrack and fire road through the Santa Monica Mountains above Malibu, starting from Las Virgenes Road in Calabasas; an early-season Western States qualifier.

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Facts checked 25 Oct 2026 against ultrasignup.com, khraces.com.

Elevation gain

4,017 m

Mountain · ↓ 4,017 m

Highest point

734 m

above sea level

Temp at start

11°C

Peaks around 15°C

Entry fee

≈ $300

Open entry

Finishers

—

typical year

Course

Loop

Cut-off: check site

Getting thereFly into LAX (Los Angeles), about 33 km from the start

Plan your trip to Calabasas

Race weekends book up early. Searches are set for the race dates.

Hotels near the start lineFri 29 Jan – Sun 31 Jan · 2 nights · closest to the start firstSee hotels on Booking.com Flights to CalabasasArrive Thu 28 Jan, fly home Mon 1 FebSee flights on Google Flights

Things to do in CalabasasKlook Mobile data in United StatesAiralo Airport transfer from LAXKiwitaxi Rent a carEconomybookings

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Course map

A detailed route is not available for this race yet. The marker shows the race location.

Elevation profile

Mountain: about 4,017 m of climbing and 4,017 m of descent. A detailed profile isn’t available for this race yet.

Race-day weather

At start

11°C

Peak during race

15°C

Humidity

60%

Chance of rain

Wind

10 km/h

30 January in past years

Historical averages for 30 January ±3 days, 2016–2025, from 05:30 for 5 hours (70 days sampled). Source: Open-Meteo / ERA5.

Finish times by age group

No data yet. We’re collecting age-group results race by race.

Runner reviews

What time could you run here?Adjust your goal time for this course’s hills and typical race-day weather.Race time calculator →

Guides for this race

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<a href="https://irun42.com/race/sean-obrien-100k" title="Sean O'Brien 100K on iRun42"><img src="https://irun42.com/badge/sean-obrien-100k.svg" width="300" height="120" alt="Sean O'Brien 100K: course, elevation and race-day weather on iRun42" /></a>

Around the same time

All races in January 2027 →

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