Trail ultramarathons in Colorado, United States
Find trail ultramarathons in Colorado, United States. Compare 14 upcoming events by date and location. Open a race guide for the course, recorded editions and official entry information where available.
Events to explore include Bridge Burner Ultra, Kessel Run Ultra and Colorado Cold Rush Ultra.
14 listed events · 14 with upcoming dates
Upcoming ultramarathons
14 matching events, earliest date first. Entry availability is shown separately.
Bridge Burner Ultra
USACanon City, Colorado
Trail races through the Royal Gorge area, starting in Canon City and following riverside paths and mountain trails.
· 50K
Race details, entry and past editions →Entry information ↗Kessel Run Ultra
USAFruita, Colorado
High-desert trail races on the North Fruita singletrack, with five distances and separate morning starts.
· 50K
Race details, entry and past editions →Entry information ↗Colorado Cold Rush Ultra
USAColorado Springs, Colorado
Trail races from Bear Creek Regional Park, with longer routes climbing historic High Drive above Colorado Springs.
· 50K
Race details, entry and past editions →Entry information ↗Sawmill Trail Runs
USAPine, Colorado
Winter trail races through Staunton State Park’s meadows, forests and granite outcrops near Pine.
· 50K
Race details, entry and past editions →Entry information ↗Rattler Trail Race
USAColorado Springs, Colorado
Trail races from Palmer Park in Colorado Springs.
· 50K · Status TBC
Race details, entry and past editions →Valkyrie Trail Race
USAColorado Springs, Colorado
Women-focused trail races in Cheyenne Mountain State Park.
· 50K
Race details, entry and past editions →Entry information ↗Weld Your Mettle Running Festival
USAEaton, Colorado
Loop running races and timed endurance challenges near Eaton.
· 100K / 50K
Race details, entry and past editions →Entry information ↗Summits Trail Runs
USAGranby, Colorado
Mountain trail races at Granby Ranch Resort, with shorter races and ultra distances.
· 50K · Status TBC
Race details, entry and past editions →Silverheels Trail Runs
USAComo, Colorado
High-altitude trail and dirt-road races around Como and the South Park Valley.
· 100K · Status TBC
Race details, entry and past editions →Pikes Peak Ultra
USAColorado Springs, Colorado
Mountain ultras and shorter trail races above Colorado Springs.
· 50K
Race details, entry and past editions →Entry information ↗Sheep Mountain Trail Runs
USAFairplay, Colorado
Mountain trail races and a half marathon based at Fairplay Beach.
· 50K · Status TBC
Race details, entry and past editions →Rock Hawk Trail Races
USACastle Rock, Colorado
Trail races on the Miller Park and Ridgeline trail systems.
· 50K · Status TBC
Race details, entry and past editions →Snow Mountain Ranch Trail Running Festival
USAGranby, Colorado
Trail races on Nordic tracks at Snow Mountain Ranch.
· 50K · Status TBC
Race details, entry and past editions →Sangre de Cristo Trail Festival
USAWestcliffe, Colorado
A mountain trail festival near Westcliffe with ultras on Saturday and shorter races on Sunday.
· 100K / 50K · Status TBC
Race details, entry and past editions →Race archive
Past races and previous editions
Looking back at a race? Browse the guides below for recorded editions. This section also includes events awaiting a new date and cancelled editions. Previous editions of races in the upcoming calendar are available through their race guides above.
No separate archived race guides are listed for this selection yet.
View full race archive (0) →Choosing a race in Colorado
The unfiltered upcoming calendar includes events in Colorado Springs (4), Granby (2), Canon City (1). Use the town filter to compare locations, then check the race guide for the start venue and organiser’s travel information.
Questions about ultramarathons in Colorado
Which trail ultramarathons are coming up in Colorado, United States?
Bridge Burner Ultra is listed for 24 October 2026. Kessel Run Ultra is listed for 7 November 2026. Colorado Cold Rush Ultra is listed for 21 November 2026. Check the race guide and organiser’s latest information before making plans.
Where can I find race entry details for Colorado, United States?
Follow the link from the race guide to the organiser or entry provider, where one is available. Check the entry deadline, eligibility and current availability there. A listed race date does not necessarily mean entries are still open.
Why has a race moved out of the upcoming calendar?
Once its listed dates have passed, a race moves to the past-editions view unless another upcoming edition is recorded. Cancelled events also leave the upcoming list. The race guide stays available, and the event returns when a new date is added.