Niwot’s Challenge

Sedalia Post Office 4195 Douglas Ave, Sedalia, CO, United States

Niwot’s Challenge is a very difficult, grass-roots, ultramarathon in Colorado’s Front Range. It is modeled after the arduous Barkley Marathons in Tennessee, and the historic More and More Difficult 50K in New Hampshire. Much of the information for this event is kept secret with an exception for those who are accepted for entry. This is […]

Furry Scurry

Washington Park - Denver 701 S Franklin St, Denver, CO, United States

The Furry Scurry is an annual, fun-filled festival and two-mile dog walk at Denver’s Washington Park to benefit the animals at the Dumb Friends League.  No matter where you scurry, every step you take and dollar you raise will make a lasting difference for the animals in our care. 

Colorado Marathon

Washington Park - Fort Collins 301 Maple St, Fort Collins, CO, United States

Marathon, Half Marathon, 10k, 5k and 3-Person Marathon Relay.  Marathon, Marathon Relay and Half Marathon runners get to run down the scenic, downhill Poudre Canyon to the finish in Old Town, Fort Collins, where we have live music and a big post-race party featuring beer from Odell Brewing Company.

Moose Mudder

Altitude Elementary School 27300 East Southshore Drive, Aurora, CO, United States

Please join us for the Annual Moose Mudder! This is a community event that will consist of an untimed 1k fun walk/run and a timed 5k followed by an optional muddy obstacle course. Get your best time, run for fun, walk with a group, form a stroller brigade, or line the streets to cheer everyone […]

Valkyrie Women’s Trail Race

Cheyenne Mountain State Park 410 JL Ranch Heights, Colorado Springs, CO, United States

Valkyrie Trail Race was created as a women only trail/ultra event,  featuring Colorado Spring’s, Cheyenne Mountain State Park.  The race offers amazing views of the city and a diverse eco-system. We have several different distances available, so everyone in your running group can participate! 50K/Marathon/30K/Half Marathon/8 Mile/4 Mile

Colorado Women’s Classic

Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United States

We are excited to return to Westminster for the 2024 Colorado Women's Classic! While focused on women, all genders are WELCOME at this event! 10M, 10K and 5K races. We will run this event rain or shine! :) This is THE race for ALL. THE. GOODIES. The Colorado Women's Classic is about the POSITIVE parts […]

Endure Trail Runs

Mueller State Park 21045 State Highway 67, Divide, CO, United States

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. […]

Samson’s Revenge Trail Race

YMCA of the Rockies - Estes Park 2515 Tunnel Rd., Estes Park, CO, United States

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 […]

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