American Heroes Run

Rogers Grove Park 220 North 95th Street, Longmont, CO, United States

The tragic events of 9/11/01 changed our nation forever. Let us not forget our proud history and those who fight everyday to keep us free. Please join us for this special day on this beautiful, flat, fast 1.05-mile loop course. The 100-mile race cutoff is 30 hours. No politics, just patriotism. - David Clark #WeAreSuperman […]

Flaming Foliage Relay

Citizens Park 17th Ave & Miner St, Idaho Springs, CO, United States

Flaming Foliage is a 165 mile overnight team relay race adventure with single track trails, from Idaho Springs to beautiful Buena Vista, over Guanella, Georgia & Fremont Passes. Since 2013, Flaming Foliage has provided teams and runners with a life changing relay adventure with experiences and views you will never forget. Each team consists of […]

Littlefoot Sprint Triathlon

Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United States

Enjoy a fun late season tri at beautiful Bear Creek Lake Park in a land before time. Set at the base of the foothills, the Littlefoot Triathlon starts off with a 750 meter swim in Big Soda Lake, with water temps expected to be approximately 70 degrees. Next, a rolling 15K bike ride on smooth […]

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 […]

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

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.

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