San Francisco, CA, United States · Saturday, October 10, 2026

Fixed Distance 50 mi

Ruth Anderson Ultra 50mi

10 days to go

80 km Distance

350 m Climbing

4.5 Grit · Challenging

37.7749° N, 122.4194° W © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Climbing rate 4 m / km Fast & Flat. This course is relatively flat and fast. Ideal for PB attempts.

Field size ~18 Tiny. You will run alone for most of it.

DUV results for the 2025 edition (50mi) — finishers only. Starters are not published, so the field was at least this big and no finish rate can be given.

Typical conditions, October

Daytime high 21°C

Night low 11°C

Rainfall Mostly dry

Daylight 11 h 29 m of light

Regional 2001-2020 average for October — NASA POWER, grid elevation 87 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	50mi	18	Aidan O'Connor · 07:06:55	Megan Cheng · 08:20:35
2024	50mi	25	James Scanlan · 05:56:48	Isabelle Defreese · 07:53:46
2023	50mi	23	Jakob Walter · 06:01:41	Elizabeth Sharpe · 09:28:46
2022	50mi	20	Chikara Omine · 05:05:41	Thia Angelo · 06:36:47
2021	50mi	7	Alessandro Kamikawa · 08:37:53	Erdenedalai Sangiragchaa · 10:16:46
2019	50mi	27	Chikara Omine · 05:51:41	Simone Angela Winkler · 08:16:12
2018	50mi	14	Jean Pommier · 06:20:14	Emi Yasaka · 07:46:14
2017	50mi	10	Chikara Omine · 05:58:20	Lisa Huerta · 11:00:32
2016	50mi	15	Chikara Omine · 05:57:12	Kelly Haston · 08:34:25
2015	50mi	16	Karl Schnaitter · 06:05:56	Kyria Wilson · 08:41:34

The field shrank 28% between 2024 (25) and 2025 (18). 28% of the 2025 field were women.

DUV results for the 2025 edition (50mi) — 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 fast & flat 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 80 km of trail with 350 m of ascent.

Trail Running Shoes 80 km of trail — cushioning that is still there in the last quarter.
Race Nutrition 80 km of self-supported fuelling between aid stations.
Hydration Vests Flask capacity for 80 km, without the bounce.
Headlamps 80 km almost certainly means running into the night.
GPS Watches Battery life first — a 80 km day outlasts most full-GPS modes.

Adidas

Terrex Agravic Speed Ultra

RunRepeat found the Adidas Terrex Agravic Speed Ultra to be perfect for midfoot and forefoot strikers, while iRunFar noted that the shoe feels incredibly effici…

★★★★★ 4.5

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

Spring Energy