Waldo 100K

AUG
1
2026
A 100K loop ultramarathon near Oakridge, Oregon, starting and finishing at Willamette Pass Ski Area. The mostly single track route climbs several peaks, offers views of Waldo Lake, and serves as a Western States qualifier and UTMB Index race.
Sat 1 Aug 2026

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Waldo 100K Ultramarathon

The Waldo 100K is a loop course held near Oakridge, Oregon, that starts and finishes at Willamette Pass Ski Area, located about 70 miles east of Eugene. The starting elevation is 5120' and the route climbs several mountains, including Fuji, The Twins, and Maiden Peak, before returning to the ski area. The course runs mostly on single track trails and includes some fairly remote sections, with multiple viewpoints along Waldo Lake.

The event is a Western States 100 Mile Endurance Run qualifier (18 hours) and is listed as an UTMB Index race for UTMB, CCC, and OCC. The race is organized by Waldo Ultras, a 501(c)(3) non profit corporation that operates under a special use permit with Willamette and Deschutes National Forests and identifies as an equal opportunity outdoor recreation service provider.

The race is described as not a beginner level ultra and entrants are advised to have prior ultramarathon experience. The event participates in Ultrasignup’s Trail to Zero program; registrants had the option to contribute to a carbon offset program to help account for event related travel, based on data about event travel emissions from prior mass participation events. Visit the organization's website for the most recent information.

Waldo 100k