Ultramarathon Guide

Waldo 100K

Waldo 100K is a remote Oregon mountain loop over Fuji, the Twins and Maiden Peak, combining high-country singletrack with a 20-hour limit each summer.

Next raceSaturday, August 1, 2026
Distance categoryUltramarathon
LocationOakridge, Oregon

Every link above goes to the race, its timing provider, or an official registration partner. Last checked July 22, 2026.

Quick facts

  • Saturday race on August 1, 2026
  • Remote 100-kilometre mountain loop
  • Fuji, Twins and Maiden Peak route
  • Western States qualifying race
Race-day forecast

Waldo 100K Race-Day Forecast

Clear on race day · 50-80°F (10-27°C) · 1% rain · 8 mph wind

Race-day forecast for Saturday, August 1, 2026 in Oakridge, Oregon, US. Checked 9:19 AM PDT race-local time. Data: Open-Meteo.

About the Waldo 100K

Waldo is an established 100K trail race centered near Oakridge and Willamette Pass. Its field, course and results history are dedicated to the 100K rather than a mixed-distance festival.

Course

The mountain loop climbs roughly 11,000 feet across Fuji, the Twins and Maiden Peak before returning to Willamette Pass. Remote singletrack and sustained climbing define the effort.

Race-day weather

Early August can bring heat, cold mountain mornings, smoke or thunderstorms. Exposed peaks and long forest sections may feel very different over the course of the day.

Past Waldo 100K dates and results

YearDateStatusResults
2026Saturday, August 1, 2026Upcoming
2025CompletedOpen results

Waldo 100K FAQ

When is the Waldo 100K?

The 2026 Waldo 100K is on Saturday, August 1, 2026.

How do I register for the Waldo 100K?

You can register for the Waldo 100K at waldo100k.org.

Race organizer or timing partner?

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