Event details subject to change. Please confirm all information via event website.
Science Stride 5K
The Friends of the National Center Science Stride 5k brings together our community for a common cause: Inspiring the next generation of scientists! This event provides an excellent opportunity for everyone who believes in the importance of STEM education to come together and support Friends of the National Center. Runners and walkers of all abilities […]
Run for the Trees
We’re helping Parks and Rec celebrate Loveland's Arbor Day. Come enjoy food trucks, live music, and a 2 mile fun run to help raise money for the tree planting fund. Each participant will receive a custom bib, custom swag (TBD), and lots of FUN!
Women’s Distance Festival 5K
The Womens’ Distance Festival is no longer an event for “women only”. This event is now a “community” event, supporting the Girls on the Run® of the Rockies. Girls on the Run is a non-profit organization that uses the power of running to change the way girls ages 8-13 see themselves and their opportunities. Girls […]
Hometown Half Marathon
Join us for the annual Hometown Half Marathon & 5k/10k! A run local-themed event that is perfect for the whole family. The fun includes great swag (designer shirt, custom medal), chip-timing, live results and awards, pacers for half marathon free photos, a "biggest team" contest, a kids' dash, great post-race food, and plenty of fun! […]
Space Race 5K
✨Prepare for launch! ✨ The Wings Space Race 5K invites you to push past your limits and chase the stars into an experience that’s truly out of this world! Join us for an all-ages run and walk benefiting Wings Over the Rockies Air & Space Museum. This space-themed event invites participants of all fitness levels—whether […]
Colorado Women’s Classic
We are excited for the 2026 Colorado Women's Classic! While focused on women, all genders are WELCOME at this event!
Super Mom Half Marathon
Celebrate the incredible strength, love, and spirit of moms everywhere at the Super Mom 5K/10K/Half Marathon! Whether you are a mother, are running for a mother, or simply want to honor the inspiring women who have shaped our lives, this event is open to everyone. This race is all about celebrating the heroes we call […]
Fruita Trail Half Marathon
This exciting half marathon course is a fun loop on the beautiful flowy single track in Fruita CO. With short steep climbs and descents featuring beautiful views of the nearby buttes and mesas runners will enjoy 13.8 miles of gorgeous open early season desert. This race is part of the Adventure Fest at 18 Road […]
Mother’s Day 5K
The Denver Mother's Day 5K – It's What Colorado Moms Do! This year, all-you-can-eat pancakes and three sausage breakfasts with OJ or coffee will be provided by Flippin' Flapjacks for all registered participants. The Denver Mother's Day 5K is excited to announce LIVE music this year! Aspire Healthy Energy Drinks is bringing their Aspiring Artists Micro Music Festival to […]
Run to the Shrine II
Join us on Saturday, May 9 or Sunday, May 10, 2026, for Run to the Shrine, Cheyenne Mountain Zoo’s annual fundraiser run/walk. This 4-mile casual run/walk winds through the Zoo and up to Will Rogers Shrine of the Sun, with leopards, lions and elephants along the way. Enjoy stunning views of Colorado Springs below while […]
Know. Grow. GO RUN. 5K
Come and GO RUN or walk our new cross country trail on campus.
Ram Party Trail Runs
With plenty of race options for everybody centered around the beautiful Rampart Reservoir in Woodland Park, Colorado, you're sure to have a good time while you take in the epic views of Pikes Peak and the front range. 55 Mile | 60K | 50K | 24K | 15K
Dog Jog 5K
The Dog Jog 5k is back and better than ever! Join the pack and run for a cause. This dog friendly 5k welcomes runners and walkers of all ages (even in dog years!) with the goal of raising funds for the pets and programs of the Cheyenne Animal Shelter.
Black Canyon Ascent
The Black Canyon Ascent 6-mile Run and Challenge Walk features a tough, scenic course starting at an elevation of 6500' and climbing almost 2,000' to the rim of the Black Canyon National Park. First run in 1977! For over 40 years, beautiful vistas and scenic surroundings have inspired people to challenge themselves and the competition in […]
Endure Trail Runs
The Endure 12-Hour is a one-of-a-kind challenging 12-Hour timed event, designed by YOU… and tiny colorful balls. Each runner will pull colored balls from a bucket, which determines the loop they’ll next run. This continues for up to 12-hours in time, and the runner’s result is the number of miles they ran within the allotted time. […]
Memorial Day Run and March
Special Forces Foundation is proud to announce the Annual Memorial Day Run & March. Be a part of the LARGEST food donation event in Colorado! The Memorial Day Run & March invites civilians, Veterans, and uniformed Military to challenge themselves in friendly competition while helping feed homeless Veterans. We have three category events to choose from […]
Tour de Victory
Join the Tour de Victory Cycling Challenge, Colorado’s premier Parkinson’s bike ride benefiting the Davis Phinney Foundation. This boutique bike ride is an opportunity to join the Davis Phinney Foundation’s inspiring community and make a positive impact on the lives of people with Parkinson's. Select your preferred route (100k, 50k, or 20k) and ride any bike you like: road bikes, e-bikes, recumbents, trikes, and more are all […]
Vallecito Lake Heavy Half
The Vallecito Lake Heavy Half Marathon is a beautiful and scenic course around Vallecito Lake. Nestled in the heart of the San Juan Mountains in Colorado, our race course takes runners completely around the picturesque Vallecito Reservoir with a special section that runs right across Vallecito Dam. If you ever wanted to run all the […]
Gluten Free Gallop
Join Denver Celiacs to raise awareness of celiac disease and all gluten-related disorders. Our 13th Annual Gluten Free Gallop 5K will take place at Clement Park in Littleton, CO, on Saturday, May 16, 2026, from 9:00 AM-12:00 PM. This year we will also be offering our very popular ROCK Fun Run again! This is a […]
Ouray Backyard Ultra
A Backyard Ultra. Complete an easy 4.167 mile course. If you finish in less than an hour—just a 14:24 pace per mile—you get to do it again at the top of the hour. The race continues hour after hour until there is only one person left. To secure the win, that person must successfully complete […]
Colfax 5K
Come run City Park in the Colfax 5K! Go for a PR in this chip-timed race – separate stroller-friendly start wave for families and walkers. And, you can run with your dog in the dog wave presented by Evolution Veterinary Specialists! Afterparty with live music. A great chance to be a part of Marathon weekend […]
Colfax Marathon
New for our 20th Year! “WOW” at Every Mile To celebrate our 20th, every mile will have a WOW for runners. That moment every mile that gives you that WOW and extra energy for the miles to come. We are inviting local musicians, artisans, drumlines, choirs, … to be part of our WOW for our […]
Mt Sopris Run-Off
The Mt Sopris Run-Off takes place in Carbondale, CO and offers two distances – 10-Miles and 28k. Historically this race has been a part of the Town of Carbondale’s Mountain Fair Weekend in late July. In 2026, the race will take place on Sunday, May 17th as part of a growing trail running festival weekend […]
Miles for Smiles 5K
The Miles for Smiles 5K is a friendly event that begins and ends on the track at the North Area Athletic Complex (NAAC) in Arvada with a scenic trek along the Fairmount Trail in the middle. Join Right Start Events on May 15th, 2022 for this 5K and Adaptive Dash.
Canine On the Creek 5K
Gather your family and friends, including your furry friends—don't forget Fido! Grab your running (or walking) shoes and join us in supporting FOCP (Friends of Charlie's Place), the Clear Creek and Gilpin County Animal Shelter, and CCMRD Youth Programs. The exciting course takes you through both paved and dirt trails along the picturesque Clear Creek. […]
Dash and Dine 5K #4
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Dash & Dine 5k run, Boulder’s favorite spring tune-up run series is back for 4 races in May at the beautiful Boulder Reservoir in Boulder, CO.
Turquoise Lake 20K
The Turquoise Lake 20K offers unparalleled mountain views as you run clockwise around scenic Turquoise Lake. The first 7.5 miles of the course consists of hilly paved road. The final 5.5 miles consist of single track dirt trail.
Farish Trail Race
Date: May 23, 2026 Location: Farish Recreation Area at 12005 Rampart Range Rd Woodland Park, CO 80863 Start times: 7:00 am – 8:00 am Distance: Half Marathon, 10K, 5K 1 Mile Kids Fun Run (Free) Prizes: Top 3 Male and Female in the Half, 10K, and 5K First 200 Finishers Receive a limited edition race […]
Samson’s Revenge Trail Race
Samson was the celebrity elk of the Rockies until he was illegally poached in 1995 on YMCA grounds. Our race runs on Samson's home turf, The YMCA of the Rockies, which his descendants still call home. The course is fast single track with a big King of the Mountain challenge slapped in the middle. This […]
Mile High Mile
The Mile High Mile Saturday, May 23 | Boulder High School The Mile High Mile is back for its 8th season—bringing a high-energy night of racing to Boulder for runners of all ages and abilities right at the heart of the Boulder Creek Festival and all the excitement of Memorial Day weekend in Downtown Boulder. […]
Please click here to submit your event for FREE to our online calendar.
We do not allow events without physical locations (IE – virtual runs, runs with locations TBD, etc…).
Please allow 48 hours after submission for an event to appear on the calendar. If you have already listed your event and would like us to update it, please contact us.