Arches Ultra
Gemini Bridges Trailhead at Gemini Bridges, Moab, UT, United StatesArches Ultra travels along the border of Arches National Park, using Bar M, Klonzo, and Klondike Trail Systems. The trails are smooth and easy at points, technical slick rock at others, and there’s even some sand to shake things up. Winter is a great time to be in Moab running, and we’ve chosen a lower […]
Big Brrrrito! 5 Mile
Chatfield State Park 11500 N Roxborough Park Road, Littleton, CO, United StatesWe host one race per month from November to March. All races are at Chatfield State Park and start at 9:00 am on Saturday mornings. Check-in starts at 8:15 am.
Rio Frio 5K
Cole Park 300 Hunt Ave, Alamosa, CO, United StatesThe Annual Rio Frio 5K on Ice is one of America’s most unique 5k races! This spectacular event is conducted entirely on the majestic frozen Rio Grande! Have you ever run on a frozen river? Come and try it out on January 29th in Alamosa.
Polar Bear 5K
Horsetooth Reservoir 4200 W County Road 38 E, Fort Collins, CO, United StatesEnjoy a beautiful run around the Horsetooth Reservoir with views of the Fort Collins Foothills. After your run, show how brave you are & take the dive into the icy reservoir water! Enjoy the after party with craft beer, overall and age group awards for the 5k, and local vendors!
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 calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]
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 calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]
Sourdough Snowshoe Race
South Sourdough Trailhead 115 Co Rd 116, Nederland, CO, United StatesThe race is intended to be a difficult and fun free of charge backcountry event; any and all plans can change due to trail conditions for the runner’s safety. Snowshoes will be required unless the race director chooses to change the requirements due to trail conditions. All racers are required to carry 20 ounces of […]
Old Man Winter Rally 5K/10K
Bohn Park 199 2nd Ave., Lyons, CO, United StatesBundle up and get ready to run and/or ride Colorado's best mixed terrain at the Old Man Winter Rally in Lyons on February 6th. Runners can crush the 10K course of single track trails, red rock canyon and gravel paths while riders can choose a 50K or 100K of dirt, snow, climbs and thrills! With a ragin' after party with hot food and cold beer, what more could you want?
Valentine’s Day 4 Mile
Washington Park - Denver 701 S Franklin St, Denver, CO, United StatesIf running is your love language - you won't want to miss our Valentine's Day 4 Mile! Find a sweetheart (or run with your sweetheart!). Share your love story! #Run4TheLoveOfIt RACE HIGHLIGHTS 💑Share your Love Story on our RunDenver Series Facebook page! The story with the most "likes" wins a special prize. 🏹Cupid's Free Kids […]
Super Half Marathon
Downtown Colorado Springs 121 S Tejon St, Colorado Springs, CO, United StatesThe streets and trails of downtown Colorado Springs are not exactly the "Frozen Tundra of Lambeau Field" but on Super Bowl Sunday, Feb.12, 2023, more than 1,500 runners will race for paydirt there in the 11th Super Half Marathon & Game Day 5K. This is Colorado Springs' Super Sunday Tradition! We have a flat and […]
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