Horsetooth Open Water Swim

Horsetooth Reservoir 4200 W County Road 38 E, Fort Collins, CO, United States

Swim a 10K, 2.4 miles, 1.2 miles, 1000 meters, or 250 meters in the Horsetooth Reservoir.  The Horsetooth Open Water Swims incorporated as an independent 501(c)3 not-for-profit organization.  Our current […]

Tri the Rock Kids Tri

Butterfield Park 3952 Butterfield Crossing Drive, Castle Rock, CO, United States

We welcome you to our 17th annual youth triathlon! Tri the Rock is designed for, and open to youth ages 5 to 18. Come for a great day of fun, food, […]

Denver Rocks Run 5K/10K

City Park - Denver 1700 N York St, Denver, CO, United States

We all know Denver is known for its world-class cultural attractions, thriving craft breweries, and red-hot music scene. Be part of the first 5K/10K running event of its kind with this rock n' roll infused run that kicks off at Civic Center Park in downtown Denver on November 6, 2021.

$45

9/11 Heroes Run

Great Lawn Park 101 Yosemite St, Denver, CO, United States

The 9/11 Heroes Run is a 5k race honoring our heroes: those lost on September 11th and in the wars since, as well as the veterans, active duty, first responders, […]

Honey Bee Hustle

Fairgrounds Park 700 S Railroad Ave, Loveland, CO, United States

Are you ready to challenge yourself? We will have a 1-mile loop open for 1 ½ hrs. Who can run the most loops in 1 ½ hrs? Who can run […]

Arapahoe County 5K Trail Run

17 Mile Horse Farm Park 8181 S. Parker Rd, Centennial, CO, United States

Lace up your sneaks for a timed 5K race beginning at Tagawa Gardens and running along the Cherry Creek Regional Trail. Walkers and all ages welcome! Funds support trail maintenance […]

Run Rabbit Run Ultra

Steamboat Springs Ski Resort 2305 Mt Werner Cir, Steamboat Springs, CO, United States

The Run Rabbit Run courses are very much like life, in that there are many, many little and not so little ups and downs in between the obvious highs and […]

CMRA South Seven

Bluffs Regional Park 10099 Crooked Stick Pl, Lone Tree, CO, United States

The course will be on wide, crushed gravel paths and, depending on the status of construction in the nearby neighborhood, potentially a little bit of single track. It's a hilly, […]

Rocky Mountain Lab Rescue 5K

Great Lawn Park 101 Yosemite St, Denver, CO, United States

The Rocky Mountain Lab Rescue Fun Run is our biggest fundraising event of the year and all of the proceeds go directly to helping our awesome dogs! We will host […]

All-Out Fallfest

Church Ranch Office Park 10170 Church Ranch Wy, Westminster, CO, United States

One of Colorado's favorite trails meets one of its most glorious parks at our 9th annual Fallfest 5K, 10K and half marathon! As the courses wind southwest along Big Dry […]

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