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

Fixed Distance 50K

Ruth Anderson Ultra 50km

24 days to go
50 km Distance
220 m Climbing
2.8 Grit · Entry level
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 ~51 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, 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.

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 50 km of trail with 220 m of ascent.

All gear guides →

Course Notes

certified 4.475 miles paved bike path with dirt shoulders (per loop)

Similar races

Other 50K trail ultras, closest in distance first.