Colorado Ultramarathons
51 upcoming ultras across Colorado, updated nightly. Want radius search and maps? Open these in the Race Finder.
When to race: ultras in Colorado
Colorado has 51 upcoming ultras over the next 12 months. Among complete calendar months, November 2026 has the most listed races, with 7. Most are around Colorado Springs, Larkspur, Fort Collins. The next one is Bridge Burner Ultra on October 24 in Canon City.
- Oct 20263 races
- Nov 20267 races
- Dec 20262 races
- Jan 20271 race
- Feb 20271 race
- Mar 20271 race
- Apr 20274 races
- May 20277 races
- Jun 20274 races
- Jul 20277 races
- Aug 20277 races
- Sep 20276 races
- Oct 20271 race
October 2026
- Sat 10/24Bridge Burner UltraCanon City, CO · 35 Miles · 50K · 35K · 10K · register ↗
- Sat 10/24The Barnyard Backyard UltraErie, CO · Timed · register ↗
- Sat 10/3111th Hour Bear Creek Backyard UltraLakewood, CO · Timed · register ↗
November 2026
- Sat 11/7Colorado 24 Hour RunFort Collins, CO · 24 Hour · 12 Hour · 6 Hour · from $90 · register ↗
- Sat 11/7Kessel Run UltraFruita, CO · 50 Mile · 40 Miles · 20 Miles · 10 Mile · 50K · registration closed · register ↗
- Sat 11/7Sandstone SixerLarkspur, CO · 6 Hour · register ↗
- Sat 11/7Sheriff's ShootoutMancos, CO · 12 Hour · 6 Hour · register ↗
- Sat 11/7The Unselfish UltraGolden, CO · 30.3 Miles · register ↗
- Sun 11/15Mountain Peacock 50kGolden, CO · 50K · Trail · register ↗
- Sat 11/21Colorado Cold Rush UltraColorado Springs, CO · 50K · Half Marathon · 10K · register ↗
December 2026
- Sat 12/5Sawmill Trail RunsPine, CO · 8.1 Miles · 16.1 Miles · 31.7 Miles · Trail · from $60 · register ↗
- Sat 12/5Thumbs Up Vertical ChallengeEstes Park, CO · 8 Hour · register ↗
January 2027
- Sat 1/2312 Hours of SunlightGlenwood Springs, CO · 12 Hour · from $65 · register ↗
February 2027
- Sun 2/7Old Man Winter Bike Rally & RunLyons, CO · 23 Miles · 40 Miles · 75K · 5K · 10K · from $49 · register ↗
March 2027
- Sun 3/28The Grand TraverseCrested Butte, CO · 40 Miles · 80 Miles · from $205 · registration closed · register ↗
April 2027
- Sat 4/3Popeye's Backyard UltraLarkspur, CO · 96 Hour · register ↗
- Sun 4/11NoCo Urban Ultra & RelayBellvue, CO · 50 Mile · 100 Mile · from $65 · register ↗
- Sat 4/17Rattler Trail RaceColorado Springs, CO · 50K · 25K · 10K · 5K · Trail · register ↗
- Sat 4/24Cheyenne Mountain Trail RaceColorado Springs, CO · 50K · 25K · 7 Miles · 4 Miles · Trail · register ↗
May 2027
- Sat 5/1Collegiate Peaks Trail RunBuena Vista, CO · 50 Mile · 25 Miles · Trail · register ↗
- Sat 5/1Greenland Trail RacesLarkspur, CO · 50K · 25K · 8 Miles · 4 Miles · Trail · from $25 · register ↗
- Sun 5/2The PilgrimageMack, CO · Ultra · register ↗
- Sat 5/8Adventure FestFruita, CO · 100K · register ↗
- Sat 5/8Valkyrie Trail RaceColorado Springs, CO · 50K · Marathon · 30K · Half Marathon · 8 Miles · Trail · register ↗
- Sat 5/15Wild Horse RunsDe Beque, CO · 50K · register ↗
- Sat 5/22Samson's RevengeEstes Park, CO · 10.45K · 25K · 50K · from $112 · registration closed · register ↗
June 2027
- Sat 6/5Weld Your Mettle Running FestivalEaton, CO · 50 Mile · 100K · 4.3 Miles · 14 Miles · Marathon · from $35 · register ↗
- Sat 6/12KowTown GravelKremmling, CO · 88 Miles · 54 Miles · 28 Miles · 16 Miles · from $85 · registration closed · register ↗
- Sat 6/12Summits Trail RunsGranby, CO · 10K · 13.9 Miles · 27.8 Miles · 33.9 Miles · Trail · from $60 · registration closed · register ↗
- Fri 6/25Race in the Clouds - Alma Dirt Festival 2027Alma, CO · 38 Miles · Marathon · Half Marathon · 22 Miles · 10K · from $10 · register ↗
July 2027
- Fri 7/9Hardrock 100 Endurance RunSilverton, CO · 100 Mile · register ↗
- Fri 7/9Silverheels Trail RunsComo, CO · 10.8 Miles · 19.1 Miles · 38.3 Miles · 53.8 Miles · 63.1 Miles · Trail · from $60 · registration closed · register ↗
- Fri 7/16Ouray 100 Mile Endurance RunOuray, CO · 100 Mile · register ↗
- Sat 7/24Creede 50/100Creede, CO · 100 Mile · register ↗
- Sat 7/24Pikes Peak UltraColorado Springs, CO · 50 Mile · 50K · 30K · 20K · register ↗
- Mon 7/26The Summit 200Frisco, CO · Ultra · register ↗
- Mon 7/26TransRockies Run - Pass to PubLeadville, CO · Ultra · register ↗
August 2027
- Fri 8/6High Five 100Lake City, CO · 100 Mile · register ↗
- Fri 8/6Wild West RelayFort Collins, CO · 200 Miles · from $700 · register ↗
- Sat 8/7Sheep Mountain Trail RunsFairplay, CO · 14.2 Miles · 33 Miles · 53.1 Miles · Trail · from $80 · registration closed · register ↗
- Sat 8/7Winter Park Trail RunsWinter Park, CO · 50K · Half Marathon · 10K · Trail · register ↗
- Sat 8/21Continental Divide Trail RunSteamboat Springs, CO · 50K · 16 Miles · 5 Miles · Trail · register ↗
- Thu 8/26La Garita 200South Fork, CO · Ultra · register ↗
- Sat 8/28Telluride Mountain RunTelluride, CO · 65 Miles · 40 Miles · 24 Miles · Trail · register ↗
September 2027
- Thu 9/2Front Range Ultra DayzeLoveland, CO · 50K · register ↗
- Fri 9/10Flaming Foliage Relay - Idaho Springs to Buena VistaIdaho Springs, CO · 165 Miles · from $680 · register ↗
- Sat 9/11Rampart Rager GravelColorado Springs, CO · 32 Miles · 44 Miles · 100K · 11.5 Miles · from $59 · registration closed · register ↗
- Sat 9/2524 Hours of Palmer LakePalmer Lake, CO · 24 Hour · register ↗
- Sat 9/25Crested Butte UltraCrested Butte, CO · 50 Mile · 55K · 35K · register ↗
- Sat 9/25Sangre de Cristo Trail FestivalWestcliffe, CO · 8 Miles · 27K · 50K · 50 Mile · 100K · Trail · from $60 · registration closed · register ↗
October 2027
- Sat 10/2Grand Valley BackyardLoma, CO · Timed · register ↗
Planning a race
- The adventure listrim to rim, the big rounds, and routes worth planning a year around
- Getting inhow entry works for the races that sell out or ballot
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