Event details subject to change. Please confirm all information via event website.
Spirit Challenge
Steamboat Springs Middle School 5100 Amethyst Drive, Steamboat Springs, CO, United StatesThe Spirit Challenge Run for Autism offers three different distances, a 10k, 5k and Kid’s Fun Run. All races are on paved roads, except for the 5k which has a short section on trail. The Kid’s Fun Run is an 800m run consisting of 2 laps around the Steamboat Springs Middle School track. The Spirit […]
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 […]
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 […]
Stem Ciders at Acreage 5K
Acreage by Stem Ciders 1380 Horizon Avenue, Lafayette, CO, United StatesJoin us for the Stem Ciders at Acreage 5k, and great, local craft cider in Lafayette on May 16, 2025 Join us for the Stem Ciders at Acreage 5k on May 16, 2025, for a 5k-ish, fun run event that starts and ends at this awesome cidery in Lafayette. Run, walk, jog - whatever goes! […]
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 […]
Wild Horse Half Marathon
Set against the breathtaking backdrop of the luxurious High Lonesome Ranch, this isn’t just a race—it’s a full weekend of adventure and celebration! Runners will enjoy a country cookout, campfires, live local music, and camping accommodations. It’s the perfect blend of rugged terrain and western hospitality, complete with a lively hoedown to round out the 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.
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.
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 […]
Narrow Gauge 10 Mile
Since 1978 the Narrow Gauge 10 Mile Run has been one of Durango’s oldest Memorial Day traditions. The 10-mile course showcases the Fort Lewis College rim, the Animas River Trail and great views of Durango! This is the longest continuously run road race in Colorado. In 2021, even with COVID, we had a temporary race […]
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