Waldo 100K

Waldo 100K is a challenging trail ultramarathon in Oregon. It starts and finishes at Willamette Pass Ski Area, located approximately 70 miles east of Eugene. The race is a 100K loop beginning at an elevation of 5,120 feet, run entirely on unpaved trails. It is designed for experienced ultrarunners, not for those attempting their first long race. The event also serves as a qualifier for the Western States 100-Mile Endurance Run and holds UTMB status, attracting participants accustomed to mountain distances, remote landscapes, and extended periods on foot. The course ascends Fuji, The Twins, and Maiden Peak, reaching a summit of 7,818 feet. Many miles traverse mostly single-track trails. Participants will have repeated views of Waldo Lake, and the route incorporates remote sections where isolation presents a challenge comparable to elevation. The event originated in 2002 and is managed by Waldo Ultras, a nonprofit organization operating under a special use permit from the Willamette and Deschutes National Forests. While elite runners have completed the course in under nine hours, most participants aim to complete the full mountain-ultra test.