Hardrock 100 Endurance Run

Memorial Park - Silverton 1800 Greene St, Silverton, CO, United States

About The Run The Hardrock Hundred Mile Endurance Run is an ultramarathon of 100.5 miles in length, plus 33,050 feet of climb and 33,050 feet of descent for a total elevation change of 66,100 feet, at an average elevation of over 11,000 feet. The run is held on a loop course on 4WD roads, dirt […]

Frisco Triathlon

Frisco Bay Marina 267 Marina Road, Frisco, CO, United States

Are you looking for a new challenge this summer? Register for the annual Frisco Triathlon featuring stand-up-paddle boarding, mountain biking, and trail running. This twist on a triathlon is open to all ability levels and encourages athletes to take on a new multi-sport event. The Frisco Triathlon was named “Best Triathlon” in Elevation Outdoors Magazine’s […]

Chase the Moon Trail Race

Mountain Vista High School 10585 Mountain Vista Ridge, Highlands Ranch, CO, United States

Chase the Moon is a 12-hour team relay and solo ultramarathon, run overnight under the light of the full moon in the Highlands Ranch Backcountry trail system (we promise some of the best views of the metro and front range). Run as a solo ultrarunner, or get your fellow moon-chasing friends for a 3-person or […]

Silver Rush 50 Mile and 25K

Leadville 124 E. Sixth Street, Leadville, CO, United States

Take on 50 miles of extreme territory that starts at 10,200 feet and reaches 12,000 feet on four separate occasions at the Silver Rush 50 Run. It will leave your lungs burning, heart pounding and eyes completely amazed — while also preparing you for the pinnacle Leadville Trail 100 Run presented by La Sportiva. New […]

All-Out Dog Days – 5K, 10K and Half Marathon

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

Get ready for some fun in the sun and a great mid-season test of your training as we bring our 11th Annual Dog Days 5K, 10K & Half Marathon! Centrally located between Denver & Boulder along with its Endless Series sidekick in December Fa La La, the beauty of our breathtaking Flatirons as a backdrop will inspire you […]

CMRA John Meade 6K

John Meade Park 2450 E Quincy Ave, Englewood, CO, United States

We will start with a loop of John Meade Park before heading onto the Cherry Hills Trail for an out-and-back short cirtcuiting the initial loop. This race will be ~3.875 miles (6k) with the same course for walkers and runners. ~115ft. The course is nearly all trail or gravel path with 0.2 miles of paved […]

Boulder Peak Triathlon

Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons.  For the veteran or first time racer, this is THE can’t miss event of the summer triathlon season, and the crown jewel of the Colorado Triathlon Series. Racers are tackling the infamous “Olde Stage” Hill, […]

High Lonesome 100

County Road 321 Nathrop, CO, United States

The High Lonesome 100 is a high flying endurance race in the Sawatch range of the Colorado Rocky Mountains. With 22,500' of vertical gain and reaching an elevation of 13,150', it's a hell of a course. The race runs in a loop through some of the most beautiful single track in the state, and takes runners on the Continental Divide and Colorado Trail, through 2 ghost towns, over 5 alpine passes, through remote basins, and over soaring ridges. This year's event takes place on July 30th.

Aspen Valley Marathon

Lions Park 101 Midland Ave, Basalt, CO, United States

Mark your calendars – Don’t miss out on this exhilarating race through the stunning landscapes of Aspen, Colorado! Join us for a one-of-a-kind experience that you’ll cherish forever. The Aspen Valley Marathon takes place in the heart of the Rocky Mountains. The marathon is a Boston Marathon qualifier, offering runners the opportunity to qualify for […]

Audi Power of Four Trail Race

Aspen Mountain 601 East Dean Street, Aspen, CO, United States

The Audi Power of Four Race Series is a premier endurance race series utilizing the unique and amazing terrain of each of the four Aspen Snowmass mountains. Each race is designed to test the limits and skills of both elite and recreational athletes. The event’s signature race is a challenging 50K Ultra is part of […]

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