Colorado Ultramarathons
49 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 49 upcoming ultras over the next 12 months. Among complete calendar months, July 2027 has the most listed races, with 8. Most are around Colorado Springs, Estes Park, Crested Butte. The next one is Mountain Peacock 50k on November 15 in Golden.
- Nov 20262 races
- Dec 20262 races
- Jan 20272 races
- Feb 20271 race
- Mar 20271 race
- Apr 20274 races
- May 20277 races
- Jun 20275 races
- Jul 20278 races
- Aug 20278 races
- Sep 20276 races
- Oct 20273 races
November 2026
- 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 · 8.2 Miles · 16.4 Miles · 32.2 Miles · Trail · from $60 · register ↗
- Sat 12/5Thumbs Up Vertical ChallengeEstes Park, CO · 8 Hour · register ↗
January 2027
- Sat 1/9BINGO! Trail RunsLakewood, CO · 8 Miles · 16 Miles · 28 Miles · Trail · from $80 · registration closed · register ↗
- 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 · 50K · 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 6/5The Great Divide UltraDivide, CO · 100 Mile · 100K · 50K · 25K · register ↗
- 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 · 100 Mile · 69 Miles · 43 Miles · 28 Miles · 8 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 · 10.7 Miles · 19 Miles · 36.6 Miles · 52.2 Miles · 63.3 Miles · Trail · from $60 · registration closed · register ↗
- Sat 7/10The Triple BypassEvergreen, CO · 118 Miles · 80 Miles · from $265 · 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 · 14.1 Miles · 33.2 Miles · 52.2 Miles · Trail · from $80 · registration closed · register ↗
- Sat 8/7Winter Park Trail RunsWinter Park, CO · 50K · Half Marathon · 10K · Trail · register ↗
- Sat 8/14Ouray 50 Mile Endurance RunOuray, CO · 50 Mile · 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 · 21.4 Miles · 50K · 50 Mile · 100K · 100 Mile · Trail · from $60 · registration closed · register ↗
October 2027
- Sat 10/2Grand Valley BackyardLoma, CO · Timed · register ↗
- Sat 10/9Sage Burner Trail RaceGunnison, CO · 50K · 28K · 15K · Trail · register ↗
- Sat 10/16Indian Creek Trail RunsSedalia, CO · 5.7 Miles · 15.1 Miles · 34.4 Miles · 50 Mile · Trail · from $40 · registration closed · 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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