Event details subject to change. Please confirm all information via event website.
Longmont Half and 5K
Longmont's only Half Marathon - now offered in the cooler month of MAY! Join the Half Marathon or 5k distance! Walkers and Runners of all abilities welcome!
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!
Colorado 13er
The Colorado 13er is THE event where the best parts of trail running and road racing combine to create a truly enjoyable, kind-to-your-body, well-supported 13.1 race! Seasoned runners and first-timers alike appreciate the excellent communication from the 13er race crew who make this event accessible for athletes of all levels.
Unicorn 5K
Ready to get off the sofa and gallop around Thornton with some friends? Yeah, you are! Come frolic with us at the Unicorn Runner 5k in Thornton to kick off your summer! You'll earn a sweet tee shirt and a flashy unicorn finisher medal!
Father’s Day Classic
It's an annual Fathers Day tradition in Arvada! All are welcome - walkers, joggers and speed demons, too! Swag includes t-shirts for ALL participants! The Fun Run is an un-timed 1 mile out and back run/walk and the MANLY MILE is open to men and is a TIMED race!
Let Freedom Run
Dress up as your favorite American Hero! This could be your mom, dad, Albert Einstein, Batman, Superman, or the Powerpuff girls! This event is all about celebrating GREAT people who do and have done GREAT things! Come be GREAT with us!
Let Freedom Run 5K
Dress up as your favorite American Hero! This could be your mom, dad, Albert Einstein, Batman, Superman, or the Powerpuff girls! This event is all about celebrating GREAT people who do and have done GREAT things! Come be GREAT with us!
Summer Splash Prairie Dog Half Marathon
Castle View High School 5254 N. Meadows Dr., Castle Rock, CO, United StatesWelcome to the Summer Splash Prairie Dog Half, 10k & 5k in Castle Rock, Colorado. Part of the Prairie Dog Half race series, join us in July as we race through Castle Rock along the East Plum Creek Trail.
Unicorn 5K
Ready to get off the sofa and gallop around Highlands Ranch with some friends? Yeah, you are! Come frolic with us at the Unicorn Runner 5k in Highlands Ranch to finish off your summer! You'll earn a sweet tee shirt and a flashy unicorn finisher medal!
Erie Half & 5K
Join us for the Erie Half and 5k! The Hometown Race Series features half marathons and 5k distance events in outlying communities outside the Denver and Boulder metro areas. LOOK UP! At the Erie event, we often see the early morning skies with dotted with delightfully colorful hot-air balloons. Whatever distance you're ready to tackle, […]
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