Event details subject to change. Please confirm all information via event website.
Canyonlands Half Marathon
The first Canyonlands Half Marathon was run on May 1, 1976 had just 22 finishers, including a dog. Today, thousands of runners come together in March to enjoy the scenic […]
All-Out Spring Fever
From the base of Table Mountain and Colorado's spectacular foothills, All-Out Multicourse presents our 11th annual Spring Fever from Jefferson County's NAAC Stadium… easily accessible from several nearby highways. Along […]
Central Park 5K
Is it spring or still winter? We'll know when we run the Central Park 5k at the end of March! Celebrate the end of winter with us on this flat […]
Behind the Rocks Ultra
Behind the Rocks Ultra starts and finishes at the Behind the Rocks Trail, along the border of the Behind the Rocks Wilderness Study Area. Moab's last hidden gem; its tall […]
Polar Plunge 5K
Are you ready for the COOLEST event of the season! Whether you're a daring plunger, a speedy 5K runner/walker, or a thrill-seeker ready to do BOTH, the Polar Plunge & […]
City Park Circuit
Denver Athletics brings you the Denver Park Circuit Series- Three races at Denver's iconic city parks with the same format: One Lap As Fast As You Can Go! Spring- The […]
All Hands on Deck Pirates 5K
This fun packed 5k is Presented by Give It Forward. Bring your entire family. It's All about community. Every child deserves a great start to the school year—but not every […]
Cryogenic Cannibal Chase
Planning on some degenerate behavior at Frozen Dead Guy Days? Start your morning off right with an 8k ripper around Lake Estes. This race is the morning pre game for […]
RMRR Spring Marathon Training Series #1
Platte River Trailhead Park Colorado Blvd and E 88th Ave, Thornton, CO, United StatesThese Marathon training races are geared towards people training for spring marathons. They are supported runs with aid stations and are timed and scored. There are both 10 mile and […]
Equinox Half Marathon
Both races start & finish at Sparge Brewing in Wellington 3999 GW Bush Unit 101, Wellington, CO 80549
Tortoise & Hare 12K
Cottonwood Glen Park 3074 S Overland Trail, Fort Collins, CO, United StatesThe Tortoise & Hare (T&H) is a low-key “handicap” series of seven races that are run monthly from October to April, typically on the first or second Sunday of the […]
Splash & Dash II
Louisville Recreation and Senior Center 900 Via Appia Way, Louisville, CO, United StatesJoin us for a Kids’ Splash & Dash Series this winter at the Louisville Rec Center! Get ready for a fun, energetic winter racing experience! Each event features an indoor […]
Cayson Pearson Memorial 5K
This annual fun run/walk (& knockout tournament if you also love basketball) is held each year to honor the memory of Cayson Pearson, award scholarships, raise funds for additional and […]
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace Format The first time you run this event, you'll establish a base time for yourself. This base time is used to generate a handicap time. The handicap time is […]
Running Up for Air
The Up For Air Series is a collection of endurance events created to support improved air quality, while having fun hiking and running on great trails with good people. Proceeds […]
Easter Bunny Hop
This family-friendly 5K is designed for runners, walkers, families, and anyone who loves welcoming spring in a fun and festive way. Whether you’re chasing a personal best or strolling the […]
Desert RATS Trail Running Festival
Desert Rats Trail Running Festival by UTMB has four unique distances, three days of racing and indescribable views of the desert. There is something for every runner. Enjoy views of […]
Run the Ranch Trail Runs
For the 5th year running and benefiting the Heart J organization, we are bringing back an amazing and beautiful trail race to Loveland, CO. You will have 6 distances to […]
NoCo Urban Ultra & Relay
A collaboration event between run.Windsor and Breakaway Athletic Events celebrating the Poudre River Trail. This long-distance race takes you on a sprawling tour of Northern Colorado via the picturesque Poudre River Trail. You'll enjoy […]
Mountain Ridge Trail Race
Mountain Ridge takes place near Highlands Ranch primarily on the Douglas County East-West Regional Trail. This gently rolling course will keep the Heart Rate pumping while offering some of the […]
RMRR Spring Marathon Training Series #2
These Marathon training races are geared towards people training for spring marathons. They are supported runs with aid stations and are timed and scored. There are both 10 mile and […]
Amasa Trail Race
Amasa Trail Race is a 25K, 15K, 10K through one of Moab's most prized trail systems. Run past petroglyphs, the famous whale rock, red rock, canyons, and the Colorado River, […]
Run Through the Decades
Step back in time and hit the streets to the soundtrack of three iconic eras at Run Through the Decades—a race that celebrates the unforgettable music of the 60s, 70s, […]
Dash for Detection 5K
Be part of a movement at Denver's City Park for our 5K event dedicated to raising awareness about oral cancer. Oral cancer can affect any area of the mouth and […]
Rockin’ on the River 5K
Hudson Gardens and Event Center 6115 S Santa Fe Dr, Littleton, CO, United StatesDust off your well-loved t-shirts and show 'em off at the Rockin' on the River 5K! Pre and post-race music and entertainment for all. Take in the view along the beautiful […]
CMRA Clear Creek 5K
This race will head west from Prospect Park on the Clear Creek trail on the north side of Clear Creek. There will be a turnaround and part way back there […]
Danico Brewing 5K
Danico Brewing Company 18490 East 66th Ave, Denver, CO, United StatesJoin us for the Danico Brewing 5k, and great, local craft beer at Danico in northeast Denver on April 11, 2026 Join us for the Danico Brewing 5k on April […]
Denver Distance Classic
Good Boys Running Club, Denver Athletics, New Balance, and Runners Roost are partnering to bring you a distance-based all-comers track meet under the lights of Randy Penn Stadium. The event […]
Spring Fling Prairie Dog Half
Apex Center 13150 W 72nd Ave, Arvada, CO, United StatesWelcome to the SPRING FLING Prairie Dog Half, part of the Prairie Dog Half Race Series. This spring-time event also features 10k & 5k distances!
Elevate Kids 5K/10K
Our mission is to help elevate kids' lives by using unique fundraising efforts to raise awareness for and donate the funds to non-profits that help kids. We do what we […]
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