Calabasas, CA, United States · Saturday, January 23, 2027

Fixed Distance 50K

Sean OBrien 50 km Trail Race

115 days away

50 km Distance

2,000 m Climbing

5.5 Grit · Challenging

34.1578° N, 118.6384° W © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 40 m / km Mountain. Significant climbing. Steep sections will require power hiking.

Time limit 14 hours 16:48 min/km average. Generous. Walkable throughout for most of the field. More forgiving than 85% of 50K races. Measured against 1034 races of the same distance. Cut-off calculator →

Field size ~107 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, January

Daytime high 17°C

Night low 10°C

Rainfall Showers likely

Daylight 10 h 17 m of light

Regional 2001-2020 average for January — NASA POWER, grid elevation 183 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2026	50km	107	Cory Fleming · 04:35:12	Tia Forsman · 06:19:12
2025	50km	80	Taylor Morris · 04:38:47	Erin Knipe · 05:23:42
2024	50km	91	Jeffrey Colt · 04:06:02	Catherine Leclair · 05:29:44
2023	50km	99	Benjamin Atkins · 04:44:50	Hayley Bricker · 06:24:12
2022	50km	47	Adrian Gonzalez · 04:41:21	Guadalupe Favela · 06:53:02
2021	50km	51	Tj Myers · 04:39:00	Lauren Ciccomascolo · 06:23:10
2020	50km	108	Aubrey Myjer · 04:16:31	Katie Asmuth · 05:08:07
2019	50km	85	Nicolas Composto · 04:05:07	Brianne Holland-Stergar · 05:04:28
2018	50km	182	Kris Brown · 03:57:23	Rebecca Murillo · 05:22:42
2017	50km	182	Michael Eastburn · 04:40:29	Emily Kalenius · 05:11:54

The field grew 34% between 2025 (80) and 2026 (107). 42% of the 2026 field were women.

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.

The Aid Station

Course-specific beta from the community

⛰️ terrain

This is a mountain course. Expect fast, runnable sections where rhythm is key.

By UltraHub Expert

👟 gear

With trail terrain, choose a shoe with moderate cushioning for optimal performance.

By UltraHub Expert

Gear for this race

Chosen for 50 km of trail with 2,000 m of ascent.

Trail Running Shoes 40 m of climb per kilometre — grip and rock protection before cushioning.
Race Nutrition 50 km of self-supported fuelling between aid stations.
Hydration Vests Pole attachment and chest-strap stability on steep ground.
Trekking Poles 2,000 m of ascent to walk up.
Headlamps A 14 h limit puts you out there after dark.

Brooks

Catamount 3

RunRepeat found the Brooks Catamount 3 to have a cozier upper that enhances the overall fit, though breathability and durability could be better. iRunFar noted…

★★★★★ 4.5

Adidas

Terrex Speed Ultra

RunRepeat found the Adidas Terrex Speed Ultra to have a grippy outsole and great lockdown, while iRunFar noted that the shoe works on a variety of trail conditi…

★★★★★ 4.5

Maurten