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Ultramarathons in Colorado

2026 and 2027 race calendar. 12 upcoming, updated daily.

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Denver36Centennial30Colorado Springs24Arvada15Fort Collins11Westminster10Loveland7Golden6Grand Junction6Boulder5Estes Park5Littleton5Durango4Glenwood Springs4Louisville4Pueblo4Steamboat Springs4Windsor4Alamosa3Aurora3Buena Vista3Crested Butte3Englewood3Longmont3
All 77 cities and towns
Denver36Centennial30Colorado Springs24Arvada15Fort Collins11Westminster10Loveland7Golden6Grand Junction6Boulder5Estes Park5Littleton5Durango4Glenwood Springs4Louisville4Pueblo4Steamboat Springs4Windsor4Alamosa3Aurora3Buena Vista3Crested Butte3Englewood3Longmont3Salida3Thornton3Alma2Bailey2Erie2Fountain2Greeley2Highlands Ranch2Idaho Springs2Leadville2Lyons2Mancos2Palmer Lake2Parker2Westcliffe2Woodland Park2Aspen1Bayfield1Bellvue1Berthoud1Broomfield1Castle Rock1Como1Divide1Eaton1Eldorado Springs1Evergreen1Fairplay1Fraser1Fruita1Georgetown1Granby1Greenwood Village1Hesperus1Johnstown1Kremmling1Larkspur1Loma1Lone Tree1Manitou Springs1Montrose1Morrison1Pagosa Springs1Palisade1Pine1Red Feather Lakes1Severance1Silverton1South Fork1Superior1Telluride1Wellington1Winter Park1
12 upcoming
Sport
AllRunning225Trail27Cycling7Triathlon7Obstacle1Other6
Distance
Any5K19210K96Half marathon93Marathon750K6Ultra12Sprint1Gravel1
November 2026

Kessel Run Ultra

Fruita, Colorado, United States
Trail50KUltra20 miles10 miles
December 2026
April 2027
June 2027
July 2027

Hardrock 100

Silverton, Colorado, United States · Jul 9 to Jul 11, 2027
TrailUltra

Silverheels Trail Runs

Como, Colorado, United States · Jul 9 to Jul 10, 2027
TrailUltra10.8 miles19.1 miles
August 2027

Wild West Relay

Fort Collins, Colorado, United States · Aug 6 to Aug 7, 2027
RunningUltra
September 2027
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