Black Squirrel Half Marathon

Lory State Park 708 Lodgepole Dr, Bellvue, CO, United States

The Black Squirrel Trail Half Marathon takes place on the wonderful trails of Lory State Park to the northwest of Fort Collins, CO. The trail half marathon course offers a tour of the outer boundaries of Lory State Park, providing breathtaking views to the east of Horsetooth Reservoir, Fort Collins and the Great Plains; and […]

$75 – $99

Sloan’s Lake Search Party Marathon

Sloan's Lake Park 1700 Utica Street, Denver, CO, United States

THE SUMMARY Did you know that the loop around Sloan's Lake in Denver Colorado is almost perfectly 2.62 miles around? Join us as we go around the lake every hour on the hour for 10 hours to complete a full Marathon or every other hour for 10 hours to complete a Half Marathon (if you decide to […]

Devil on the Divide 50K/22K

Minton Park Cemetery Rd, Empire, CO, United States

We are pleased to present one of the most beautiful and challenging trail racing events in the state of Colorado with breathtaking (literally and figuratively) views of Clear Creek County and the Continental Divide. Participants will reach a top altitude over 13,000 feet. The 50K course climbs over 6500 feet.  Due to the difficulty and […]

Harvest Moon Long Course Triathlon

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

The Harvest Moon Triathlon the 23rd edition of this event takes place at the beautiful Boulder Reservoir on September 10th, 2022.  Est. in 2000 this Colorado classic  provides the veterans to beginners a challenging, affordable, and competitive race with a local flavor.  Whether this is your final event of the season, or a tune-up for […]

Waneka Classic Community 5K

Waneka Lake Park 1600 Caria Dr, Lafayette, CO, United States

A free, timed 5K, open to the public, held prior to the Centaurus Cross Country Invitational. Proceeds from the World Famous Concessions Stand and T-shirt sales benefit the Centaurus Cross Country Team. Stick around and watch Colorado's best student-athletes run the same course. A note about parking: Parking is available throughout the Waneka Lake residential […]

RexRun 5K for PAWSitivity

Arapahoe County Fairgrouds 25690 E Quincy Ave, Aurora, CO, United States

The RexRun 5K is a 5K run/walk to spread mental health awareness and #PAWSitivity in schools with the help of more Therapy K-9's like Arapahoe County Sheriff's Office K-9 Rex. This year's event is at Dove Valley Park in Centennial on August 6th.

$30 – $60

PPRR Nielson Challenge

North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United States

Race 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 […]

Lake Nighthorse Triathlon

Lake Nighthorse 1795 CR 210, Durango, CO, United States

Sprint Triathlon - 750 Meter Swim, 12.5 Mile Bike (road), 3.1 Mile Run

Desert’s Edge Triathlon

Imondi Wake Zone 1583 Cipolla Road, Fruita, CO, United States

Highline Lake State Park has been drained for 2024 to assist in the park's efforts to eradicate invasive zebra mussels. Therefore, the 2024 Desert's Edge triathlon series will take place at Imondi Wake Zone in Fruita, CO.

PPRR Nielson Challenge

North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United States

Race 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 […]

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