Diablo 50 km Trail Run

Race completed

50 km Distance

not publishedn/a Climbing

2.5 est Grit · Entry level

Calculated from 50 km alone — the organiser has not published an elevation profile. Read 2.5 as a floor, not a verdict.

37.9410° N, 121.9358° W © OpenFreeMap © OpenMapTiles Data from OpenStreetMap

What the course asks

Time limit 9 hours 10:48 min/km average. Generous. Walkable throughout for most of the field. Climbing is unpublished, so this pace is a ceiling on the effort, not a measure of it. Tighter than 71% of 50K races. Measured against 1034 races of the same distance. Cut-off calculator →

Field size ~29 Small. Long stretches with nobody in sight.

DUV results for the 2025 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, September

Daytime high 29°C

Night low 11°C

Rainfall Dry — rain unlikely

Daylight 12 h 51 m of light

Regional 2001-2020 average for September — NASA POWER, grid elevation 105 m. Not a forecast.

Results history

Year	Race	Finishers	Men's winner	Women's winner
2025	50km	29	Jeffrey Clark · 05:38:42	Katy Pieri · 06:11:27
2024	50km	13	Jeffrey Clark · 06:11:49	Michelle M. Ho · 08:56:17
2023	50km	30	Brian Johnson · 05:58:01	Jennifer Doias · 08:12:47
2022	50km	25	Petr Martynov · 04:57:52	Kirsten Kanarr · 06:32:30
2021	50km	16	Jordi Moncada Elias · 05:31:47	Rebecca Heymann · 06:23:52
2019	50km	33	Michael Fink · 05:55:14	Julie Neumann · 06:19:16
2018	50km	32	Robert Ressl-Moyer · 04:42:20	Suzanne Farrell · 06:09:52
2017	50km	24	Robert Ressl-Moyer · 05:05:39	Rose Kennedy · 06:42:57
2016	50km	31	Matt Craven · 05:18:59	Sharon Yamauchi · 06:03:42
2015	50km	42	Gernot Helferich · 05:34:19	Ayako Murai · 06:04:47

The field grew 123% between 2024 (13) and 2025 (29). 24% of the 2025 field were women.

DUV results for the 2025 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

👟 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.

Trail Running Shoes 50 km of trail — cushioning that is still there in the last quarter.
Race Nutrition 50 km of self-supported fuelling between aid stations.
Hydration Vests Flask capacity for 50 km, without the bounce.
GPS Watches Battery life first — a 50 km day outlasts most full-GPS modes.

La Sportiva

Prodigio Pro

RunRepeat found the La Sportiva Prodigio Pro to have a secure, locked-in fit due to its premium upper, and also praised the shoe's energetic ride, particularly…

$225 ★★★★★ 4.6

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

Spring Energy