50K ultramarathons in Colorado, United States

Alpine Loop course through historic mining ghost towns, reaching 12,930 feet at California Pass and descending to Silverton, total gain 4,400 feet

Challenging 50K ultra crossing all four Aspen Snowmass mountains on singletrack and dirt roads, featuring demanding elevation and scenic mountain terrain.

50-mile route from Bear Creek Regional Park through High Drive, Cheyenne Canon, and notable landmarks including Seven Bridges and Helen Hunt Falls

High-altitude courses over 10,600 feet, technical trails and remote forest service roads, striking mountain views, and challenging wilderness terrain

Aspen 50K route featuring demanding ascents, out-and-back to McNamara Hut, diverse terrain, and Elk Mountains scenery, starting at Rio Grande Park

High-alpine course over flowing singletrack and rugged mountain paths, finishing in town with mountain views and community atmosphere.

Packed dirt and single-track trails with lakeside views and mountain vistas around Standley Lake, under Colorado’s open skies

Challenging 50K and 50M trail races in Roxborough State Park with steep climbs, technical terrain, minimal shade, and substantial elevation gain.

Aspen and pine forest trails, panoramic Yampa Valley views, 5,500 feet of elevation gain, summit climbs above 10,000 feet, scenic Long Lake section

Undulating trails through Miller Park and Ridgeline, moderate elevation changes, scenic course with Castle Rock views

Historic mining district course with ascents to Miners Creek, scenic trail descents, landmark passages, and strict pace cutoff times

Rolling hills, golden aspen groves, expansive mountain views, and varied terrain on a challenging 50K trail course in Granby, Colorado

Point-to-point mountain course over scenic singletrack and dirt paths, exceeding 13,000 feet elevation with more than 6,500 feet of climb through Clear Creek’s,

High-country ultramarathon with 50 Mile and 50K routes on singletrack and dirt roads, challenging climbs, moose-filled forests, and sweeping mountain views

Rugged decommissioned roads and newly reopened trails from La Veta, with panoramic views of dikes, buttes, and the Spanish Peaks

Rolling terrain on the Rainbow Trail beneath the jagged peaks of the Sangre de Cristo mountains, along the Southern Colorado Rockies wilderness boundary.

High alpine vistas and desert-style singletrack, 4,000 feet of climbing, scenic forest roads, and views of the Collegiate Peaks near Buena Vista, Colorado

High-alpine 50k with a 7,000-foot climb to 13,150 feet, sweeping Sawatch Range views, panoramic singletrack, and miles on the Colorado Trail.

Rugged 50k trail route with significant elevation gain, technical terrain, and alpine vistas near Rocky Mountain National Park