Event details subject to change. Please confirm all information via event website.
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
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 […]
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 […]
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 […]
ASDAsh 5K to Beat Tooth Decay
Join us for the University of Colorado School of Dental Medicine's 6th Annual ASDAsh 5K to Beat Tooth Decay! We are excited to share that our 5K course has been […]
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 […]
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 […]
Boulder Track Series #1
Niwot High School 8989 Niwot Road, Niwot, CO, United StatesWe are pleased to offer 2 x Spring track meets (4/12 & 5/3), for middle distance and distance runners, that will be conducted similarly to the BMC (British Milers Club) […]
All-Out Beat the Heat
One of Colorado's favorite trails meets one of its most glorious parks at our 11th annual Beat the Heat! As courses wind southwest along Big Dry Creek Trail, the remarkable […]
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 & […]
Canceled Great Western Trail Race
The Great Western Trail is a wide unpaved trail located in rural Weld County in Northern Colorado. The trail connects to the Windsor Trail system on the northeast edge of […]
Canceled Sky Rim Duathlon
FORMAT: 3 mile run - 12.5 mile bike - 3 mile run WHERE: Fort Lewis College. Most of the bike and run courses utilize FLC roads/grounds and Rim Drive. See […]
Do Not Stop Half Marathon
Question: Is it supposed to be DO NOT STOP, or DONUT STOP? Answer: YES! Like Running or Walking? Love Donuts? This race is for you! Join us for the annual […]
Earth Day 5K
Please join the Durango Running Club for the inaugural Earth Day 5K! The race will be on 04/18/26 at 8:30 AM at Rotary Park in Durango. Runners and walkers will […]
Woody’s Tortoise And Hare 5K
This race is a true handicap event in that it measures your fitness level based on your age, sex, height and weight! Following a victory at the Boston Marathon, Bill […]
Rocky Run 5K
All donations raised from this competition and our Rocky Run 5K go directly to Eldorado's PTO, which supports the school in a wide variety of ways. A few things that […]
Horsetooth Half Marathon
Welcome to the 53rd running of the Horsetooth Half Marathon. Your race will take you on a scenic point-to-point journey from Hughes Stadium, the former home of the CSU Rams, […]
Do Not Stop Half Marathon
Question: Is it supposed to be DO NOT STOP, or DONUT STOP? Answer: YES! Like Running or Walking? Love Donuts? This race is for you! Join us for the annual […]
Fairmount 5K
The Fairmount 5k has been an essential fundraiser for almost 30 years at Fairmount Park. This year, following the 5k run, walk and fun run we invite you to stay […]
Thelma and Louise Trail Race
Because a girls weekend should include an exciting challenge, we present Thelma and Louise Marathon Half Marathon and 15K! There is also a marathon and 50K option! Bring your best […]
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