Waldo 100K
Willamette Pass, United States • 1 Aug 2026
Waldo 100K
The Waldo 100K Ultramarathon is a loop course that begins and ends at Willamette Pass Ski Area near Oakridge, Oregon. The ski area sits at elevation 5120' and is about 70 miles east of Eugene, Oregon. The route climbs several named peaks including Fuji, The Twins, and Maiden Peak before returning to the ski area.
The course is mostly single track and includes some fairly remote sections. The route passes multiple viewpoints of Waldo Lake. The event is described as not a beginner level ultra; organizers recommend that entrants have prior ultramarathon experience.
For the 2026 edition a lottery was used to allocate entries and the organizers offered an optional contribution to a carbon offset program called Trail to Zero. When registering for the lottery entrants had the option to contribute one dollar or more to the Trail to Zero program. The event page cites a statistic that 98.5 percent of an event's carbon footprint came from participant travel at a sample of mass participation events. Visit the organization's website for the most recent information.