Event details subject to change. Please confirm all information via event website.
Rock Hawk Trail Race
Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak up the amazing views. This is an excellent race for both first-time and veteran trail runners, and provides a nice test for those who are […]
Boulder Sunset Triathlon
Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local favorite. For the 5th year in a row we are the proud host of the Mountain Collegiate Conference race and the USAT Duathlon Race Series. […]
Boulder Sunset 5K/10K
The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, and start training for the end-of-the-summer endurance festival with BBSC.
Thirsty 13 Half Marahton
It's a race. It's a Brewfest. It's the Thirsty 13 Half Marathon! Are you thirsty for gorgeous scenery? You won't find a course more beautiful than this one. With the majestic La Plata mountains in the background, you'll cruise through the lush pastures of Wildcat Canyon and past the pristine waters of Lake Nighthorse. This […]
RMRR Fall Marathon Training Series
Riverwalk Ballfields 9830 Riverdale Rd, Thornton, CO, United StatesRMRR’s Marathon Training Series provides 10M and 20M races that are low cost, friendly, fully supported, and officially timed. All you need to do is focus on your running! Our races fit perfectly in training schedules for Colfax, Boston, New York, Chicago, and other full and half marathons. Everyone is welcome at our MTS races: RMRR members, […]
Bluffs 8K Trail Run
Prairie Sky Park 10249 Ridgegate Circle, Lone Tree, CO, United StatesThe Bluffs 8K Trail Race has rolling hills and beautiful views as you run or walk through the Bluffs Regional Park. The race will start/finish near the Prairie Sky parking lot o n August 28th.
Grand Traverse Mountain Run
The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, runners travel 40 miles across the Elk Mountains with over 6,000′ of elevation gain.
Labor Day Half Marathon
Celebrate the last blast of summer at the Labor Day Half Marathon. Sweat your socks off and let summer have its last hooray at Parker's Salisbury Park just a few miles southeast of Denver. There's a distance to meet every taste with a half marathon 10K and 5K.
Littlefoot Sprint Triathlon
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 […]
CMRA South Seven
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, but very run-able course, a few ups and downs during this 7 mile course! We'll travel "the wrong way" around the standard Bluffs route before […]
Please click here to submit your event for FREE to our online calendar.
We do not allow events without physical locations (IE – virtual runs, runs with locations TBD, etc…).
Please allow 48 hours after submission for an event to appear on the calendar. If you have already listed your event and would like us to update it, please contact us.