Ultra Races in Colorado

NoCo Urban Ultra & Relay

Sun, Apr 12 · Bellvue, CO Bellvue

Ultra 50 Mile (Relay)50 Mile (Individual)100 Mile (Individual) +1

From $100 Open Closing Soon

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Boulder Track Series Meet 1

Sun, Apr 12 · Longmont, CO Longmont

Road 2-Mile - 20 years & older2-Mile - 13 to 19 years800m - 12 & under +14

From $10 Open

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Donot Stop Half Marathon (5k/10k) - Colorado Springs

Sat, Apr 18 · Colorado Springs, CO Colorado Springs

Virtual 1 Mile5K10K +5

From $0 Open Closing Soon 5 spots left

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2026 Fairmount Fit Fest

Sun, Apr 19 · Golden, CO Golden

Virtual Fairmount 5k WalkFairmount 5K RunVirtual 5k Run/Walk +4

From $20 Open Closing Soon

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DoNot Stop Half Marathon (5k/10k) - Denver

Sun, Apr 19 · Westminster, CO Westminster

Virtual 1 Mile5K10K +4

From $17 Open Closing Soon 5 spots left

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Runs With Scissors Races

Sat, Apr 25 · Brighton, CO Brighton

Virtual Half MarathonMarathon50K Ultra Marathon +3

From $35 Open Closing Soon 35 spots left

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Unicorn 5k (Denver-East)

Sun, Apr 26 · Denver, CO Denver

Road 5k1/2 Mile(ish) Saunter

From $13 Open

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Greenland Trail Races

Sat, May 2 · Larkspur, CO Larkspur

Ultra 4M Trail Races8M Trail Race25K Trail Race +3

From $25 Open

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Frank Shorter Track Classic

Sun, May 3 · Longmont, CO Longmont

Road 1-Mile - 13 to 19 years1-Mile - 12 & under1-Mile - 20 years & older +14

From $10 Open

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Quad Rock 25 & 50 Mile Trail Races

Sat, May 9 · Bellvue, CO Bellvue

Trail Quad Rock 25Quad Rock 50

From $125 Open

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Hometown Half Marathon & 5k/10k - Colorado Springs

Sat, May 9 · Colorado Springs, CO Colorado Springs

Virtual 1 Mile5kVirtual Run +4

From $17 Open Closing Soon 5 spots left

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Hometown Half Marathon & 5k/10k - Denver

Sun, May 10 · Denver, CO Denver

Virtual 1 Mile5k10k +4

From $17 Open Closing Soon 5 spots left

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Colorado Women's Classic - Westminster

Sun, May 10 · Westminster, CO Westminster

Road 5k10k10 Miler

From $35 Open

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Miles for Smiles 5K

Sun, May 17 · Arvada, CO Arvada

Virtual Miles for Smiles 5K - Virtual RaceMiles for Smiles 5KJordyn's Adaptive Dash - open to children who have received adaptive equipment from Two Angels Foundation

From $0 Open

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Weld Your Mettle Running Festival

Sat, May 30 · Eaton, CO Eaton

Virtual 7k walk or run (4.3 miles)7K Ruck (4.3 Miles)14 Mile +10

From $35 Open

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OUTLAW GRAVEL

Sun, May 31 · Steamboat Springs, CO Steamboat Springs

Short CourseLong Course

From $165 Open

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BRR All-Comers Summer Track & Field Series #1

Thu, Jun 11 · Boulder, CO Boulder

Road 3000m100M200M +11

From $0 Open 15 spots left

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The Hundo and The Hundito

Sat, Jun 13 · Bailey, CO Bailey

Hundito VolunteerThe Hundito (64KM)The Hundito Fundraising Entry +6

From $75 Open 3 spots left

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KowTown Gravel

Sat, Jun 13 · Kremmling, CO Kremmling

KTG Cow DogKTG The CalfKTG Calf E bike +3

From $85 Open

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Garden of the Gods Little Horn and Big Horn Kids Races

Sun, Jun 14 · Colorado Springs, CO Colorado Springs

Open

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Freedom Tour Classic

Sat, Jun 20 · Fort Collins, CO Fort Collins

5K Walk15 Mile25 Mile w/T-shirt +3

From $25 Open

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BRR All-Comers Summer Track & Field Series #2

Thu, Jun 25 · Boulder, CO Boulder

Road Steeplechase (3000 + 2000)100m200m +11

From $20 Open 15 spots left

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Pearl Street Mile

Sat, Jun 27 · Boulder, CO Boulder

Road Pearl Street MileKids 800m

From $15 Open

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Let Freedom Run 5k - LONGMONT

Sat, Jul 4 · Longmont, CO Longmont

Road 5k Run/Walk

From $30 Open

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Let Freedom Run 5k/10k - Louisville

Sat, Jul 4 · Louisville, CO Louisville

Road 5k10k

From $30 Open

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Red, White, and WARRIOR 5K

Sat, Jul 4 · Grand Junction, CO Grand Junction

Road Red, White, and WARRIOR 5KLittle Sparkler Sprint

From $10 Open

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BRR All-Comers Summer Track & Field Series #3

Thu, Jul 9 · Boulder, CO Boulder

Road 5000m100M200M +10

From $20 Open 15 spots left

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Silverheels Trail Runs

Fri, Jul 10 · Como, CO Como

Trail 10-Mile19-Mile60k +3

From $50 Open

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Heatwave Half Marathon - Denver

Sat, Jul 11 · Denver, CO Denver

Virtual 1 Mile5 K10 K +5

From $17 Open 5 spots left

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The Triple Bypass

Sat, Jul 11 · Evergreen, CO Evergreen

Double BypassTriple Bypass

From $245 Open

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Heatwave Half Marathon - Colorado Springs

Sun, Jul 12 · Colorado Springs, CO Colorado Springs

Virtual 1 Mile5 K10 K +5

From $17 Open 5 spots left

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High Lonesome 100

Fri, Jul 17 · Nathrop, CO Nathrop

Ultra 100 Miler

From $465 Open

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BRR All-Comers Summer Track & Field Series #4

Thu, Jul 23 · Boulder, CO Boulder

Road 100M200M400M +10

From $20 Open 15 spots left

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Never Summer 100km & 60km

Fri, Jul 24 · Walden, CO Walden

Ultra Never Summer 60kmNever Summer 100kmThe Double (60km & 100km)

From $175 Open 20 spots left

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Audi Snowmass 50 Mountain Bike Race

Sat, Jul 25 · Snowmass Village, CO Snowmass Village

25 Mile Solo Racer (1 Lap)50 Mile Team of 2 (2 laps)50 Mile Solo Racer (2 laps)

From $115 Open 60 spots left

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Spirit of the West 5K Run/Walk

Sun, Jul 26 · Golden, CO Golden

Road 5K Run/Walk

From $35 Open

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Wild West Relay

Fri, Jul 31 · Fort Collins, CO Fort Collins

Wild West Relay - Get Your Ass Over the Pass - 12 person team (7-12 runners)Wild West Relay - Get Your Ass Over the Pass - High School TeamWild West Relay - Get Your Ass Over the Pass - Ultra team (4-6 runners) +1

From $660 Open

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Sheep Mountain Trail Runs

Sat, Aug 1 · Fairplay, CO Fairplay

Trail Half Marathon50k50-Mile

From $70 Open

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BRR All-Comers Summer Track & Field Series #5

Thu, Aug 6 · Boulder, CO Boulder

Road 100M200M400M +9

From $20 Open 15 spots left

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Summer Sizzler- Denver

Sat, Aug 8 · Thornton, CO Thornton

Virtual 1 Mile5k10k +4

From $17 Open 5 spots left

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Summer Sizzler- Colorado Springs

Sun, Aug 9 · Colorado Springs, CO Colorado Springs

Virtual 1 Mile5K10K +4

From $17 Open 5 spots left

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2026 CKF Leadville Trail 100 MTB

Sat, Aug 15 · Leadville, CO Leadville

2026 CKF Leadville Trail 100 MTB - Extended With House2026 CKF Leadville Trail 100 MTB - Extended No House

From $0 Open

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Golden Harvest Half Marathon & 5k/10k - Denver

Sat, Sep 5 · Denver, CO Denver

Virtual 1 Mile5k10k +4

From $17 Open 5 spots left

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Golden Harvest Half Marathon & 5k/10k - Colorado Springs

Sun, Sep 6 · Colorado Springs, CO Colorado Springs

Virtual 1 Mile5K10K +4

From $17 Open 5 spots left

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Flaming Foliage Relay - Idaho Springs to Buena Vista

Fri, Sep 11 · Idaho Springs, CO Idaho Springs

Flaming Foliage Relay - 10 person Team (6-10 runners)Flaming Foliage Relay - Super Ultra (1-3 runners)Flaming Foliage Relay - Ultra Team (4-5 Runners)

From $623 Open

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