Waldo 100K is a 100km ultra marathon in Oakridge, United States. Distance: 100km. Elevation: 4,300m D+. Difficulty: challenging (Challenge Rating 48/100). DNF rate: 20%. Time limit: 24h. Surface: trail. Established 2011.
Waldo 100K
Oakridge, Oregon, United States
"100km in the Oregon Cascades. Alpine lakes, old-growth forest, and volcanic lava fields on the Pacific Crest Trail."
One of the most scenic 100K courses in America — alpine lakes, PCT singletrack, and lava fields in the Oregon Cascades.
The Course
An out-and-back along the Waldo Lake Trail and Pacific Crest Trail in the Oregon Cascades. The course runs past pristine alpine lakes, through old-growth forest, and across volcanic lava fields. One of the most scenic 100K courses in North America.
mountainous
out-and-back
8
Runner Experience
Standard aid station support with food, drinks, and basic medical assistance at regular intervals.
Mountain village finish with local food, drinks, and a relaxed post-race atmosphere. The setting rewards the effort.
Race Day Weather
20°C
6° – 30°
30%
5%
Oregon Cascades summer — warm, dry days with cold nights at altitude. Smoke from wildfires possible in August.
Stats & Records
2011
200
14:00:00
08:27:00
David Laney (2019)
10:10:00
Camelia Mayfield (2022)
Entry
$175
January
instant
Lore & Trivia
Waldo 100K runs through the Oregon Cascades — a volcanic mountain range of old-growth forest, alpine lakes, and lava flows. The course circles Waldo Lake (one of the purest lakes in the world) and crosses the Cascade divide through terrain that showcases the Pacific Northwest at its most magnificent. Oregon trail runners consider the Cascades sacred ground, and Waldo — with its combination of accessibility and wilderness beauty — is one of its premier events.
- ▸ Waldo Lake is one of the purest lakes in the world — visibility exceeds 30 meters.
- ▸ The course crosses ancient lava flows from the Cascade volcanoes.
- ▸ The Pacific Crest Trail sections are some of the most scenic stretches of the famous 2,650-mile trail.
- ▸ Waldo sells out instantly and has become a bucket-list Pacific Northwest ultra.
- ▸ Established in 2011.
Oregon's Cascades at their finest — Waldo Lake, old-growth forest, and volcanic peaks on the horizon.
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Frequently Asked Questions
How long is Waldo 100K? +
Waldo 100K is a 100km (100km) ultra marathon with 4,300m of elevation gain. The course is out-and-back on trail terrain.
How hard is Waldo 100K? +
Waldo 100K is rated challenging with a Challenge Rating of 48/100 (Challenging). The DNF rate is 20%. Runners have 24 hours to finish.
What is the weather like at Waldo 100K? +
Average temperature is 20°C (range 6°C to 30°C) with 30% humidity and a 5% chance of rain. Oregon Cascades summer — warm, dry days with cold nights at altitude. Smoke from wildfires possible in August.
Are crew and pacers allowed at Waldo 100K? +
Crew access is allowed. Pacers are allowed after 60km.
What is the course record for Waldo 100K? +
The men's course record is 08:27:00 set by David Laney in 2019. The women's course record is 10:10:00 set by Camelia Mayfield in 2022.
What is the average finish time for Waldo 100K? +
The average finish time is 14:00:00. About 200 runners finish each year. The DNF rate is 20%.
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