Event details subject to change. Please confirm all information via event website.
Horsetooth Open Water Swim
Swim a 10K, 2.4 miles, 1.2 miles, 1000 meters, or 250 meters in the Horsetooth Reservoir. The Horsetooth Open Water Swims incorporated as an independent 501(c)3 not-for-profit organization. Our current […]
RMRR Fall Marathon Training Series #2
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 […]
Lead King Loop
Join us for a great day of running through the spectacular fall colors in the heart of the Elk Mountain Range. Run, walk, or hike the 25k loop around Lead King […]
Tri the Rock Kids Tri
We welcome you to our 17th annual youth triathlon! Tri the Rock is designed for, and open to youth ages 5 to 18. Come for a great day of fun, food, […]
Nun Run Half Marathon
Do you support life at all stages from conception until natural death? Do you believe every human being should be treated with the utmost dignity and the respect they deserve? […]
RMRR 5K/10K
Riverwalk Ballfields 9830 Riverdale Rd, Thornton, CO, United StatesEveryone – slow, fast, or in-between – can win at RMRR Trophy Series races. With our handicap scoring system, we predict YOUR finish time based on recent running results, giving you a great […]
El Grito 5K
The 31st El Grito 5k run & walk will start at 9:00 am on the MSU Auraria Campus, 900 Auraria Parkway, Denver, CO 80204. Race fee is $30/$35 on race […]
Colorado Run for the Fallen
Join us at Palmer Lake Regional Recreation Area for the Annual Colorado Run for the Fallen—a 6-hour untimed run/walk/ruck hosted by the Honor and Remember – Colorado Chapter. This moving […]
9/11 Heroes Run
The 9/11 Heroes Run is a 5k race honoring our heroes: those lost on September 11th and in the wars since, as well as the veterans, active duty, first responders, […]
Honey Bee Hustle
Are you ready to challenge yourself? We will have a 1-mile loop open for 1 ½ hrs. Who can run the most loops in 1 ½ hrs? Who can run […]
Tiger Prowl 5K
The Tiger Prowl 5K is a fabulous annual community event and tradition run by the Lakewood High School Foundation to support all the talented and ambitious student programs offered. All […]
Cabin Creek Fall 5K
Cabin Creek Brewing 577 Twenty-Second Street, Georgetown, CO, United StatesJoin us for The Cabin Creek 5k on September 13, 2026, for a 5k-ish, fun run event that starts and ends at this awesome taproom in Georgetown. Run, walk, jog […]
Canceled Flying Falcon Downhill Mile
Looking to run the fastest mile you possibly can? Dropping 220 feet, the Flying Falcon Downhill Mile will allow you to run the absolute fastest mile possible. Taking place on […]
Lakewood Trail Running Series III
Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United StatesThe popular trail running series in Bear Creek Lake Park takes place weekly in September. Different routes allow participants to explore all areas of the park. Racers can compete against […]
Run Rabbit Run Ultra
The Run Rabbit Run courses are very much like life, in that there are many, many little and not so little ups and downs in between the obvious highs and […]
Severance Glow 5K
Welcome to Severance's Severance Days 5K presented by Severance Middle School the Town of Severance with proceeds benefitting Severance Middle School. Held at the Severance Community Park. Severance Days 5K […]
Break of Dawn Trail Race
Be part of BeyondHome's first trail race at North Table Mountain! This scenic and challenging 8.6-mile race supports BeyondHome in helping families build stable, self-sufficient futures through housing, education, and […]
Pikes Peak Ascent
The Pikes Peak Marathon, founded in 1956, is the oldest continually held marathon in the United States, taking runners from Manitou Springs, Colorado, to the summit of Pikes Peak at […]
Superhero 5K/10K
A beloved community tradition, the Superhero Run invites runners, walkers, and families of all ages to suit up in their favorite superhero costumes and race for a cause. With a 5K, […]
Marine Memorial 5K
The Marine Memorial 5K benefits the United States Marine Corps Memorial and helps us maintain the flags, lights, and physical aspects of the site. Your help is greatly appreciated to […]
Run the Rockies Half Marathon
The Run the Rockies Road 10k and Half Marathon will feature the traditional Run the Rockies Road Race course with runners starting near Copper Mountain; runners will follow the paved […]
All-Out Fallfest
One of Colorado's favorite trails meets one of its most glorious parks at our 9th annual Fallfest 5K, 10K and half marathon! As the courses wind southwest along Big Dry […]
Ouray Mountain Trail Run
Thank you for your interest in joining us for this fantastic 13-mile run in the mountains of Ouray. You will be challenged but also enthralled by the incredible views and […]
Wolf Creek Wrangle
Take a step back in time and run or hike where the settlers of the west once walked! These trail runs are hosted by the historic Eaton's Ranch, the country's […]
Canceled ColorFest Color Run 5K
Brilliant colors will be flying at Pagosa Springs' iconic ColorFest Color Run 5k. As participants venture out on the course, vibrantly hued hot air balloons will be filling the skies […]
Sunlight Showdown Half Marathon
Sunlight Mountain Resort 10901 County Road 117, Glenwood Springs, CO, United StatesWelcome to the Sunlight Mountain Race Series, where mountain air, winding trails, and a vibrant community come together for an unforgettable summer of running. For seven years, our half marathon […]
Battle by the Brook
The 9th Annual Battle by the Brook Adventure Race will be held on September 19th, 2026 at Camp Shady Brook, in Deckers, CO. This is our favorite fundraiser! With your […]
Blisters & Brews 5K
Blisters & Brews is a 5k Fundraiser Race on the morning of Saturday, September 14, giving Festival attendees the opportunity to exercise before the Festival. Presented by the Telluride Blues […]
Beulah Challenge
Due to the Aspen Acres Fire, the half marathon had been cancelled in 2026. The Beulah Challenge, which started in 1996, is a 5K, 10K, and half-marathon run near Beulah, a small […]
Miles 4 Madison 5K
Join us in Sterling Ranch for the Miles 4 Madison 5k/1k fun run. Miles 4 Madison is a 5K/1K fun run sponsored by Sterling Ranch Cab. Miles 4 Madison’s goal […]
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