Event details subject to change. Please confirm all information via event website.
Breakthrough T1D Walk
As the leading global type 1 diabetes (T1D) research and advocacy organization, Breakthrough T1D has played a crucial role in nearly every major T1D breakthrough in history. No organization does more to improve everyday life with T1D—from therapy development and access, to expanding research, advocacy, and community support. Breakthrough T1D Walk is the world’s largest […]
Durango Marathon
The inaugural Durango Marathon, Half Marathon, and 5k debuts on October 11, 2026, and you are invited to experience one of Colorado’s most beautiful mountain towns at the height of fall. Set against crisp high-country air and peak autumn foliage, this road race showcases scenic paved routes winding through and around Durango, with a start […]
Run the Rocks
We are hosting our 21st annual Run the Rocks on October 11th from 8:15AM - 1PM. We’re biased, but we think it’s an event no one should miss! Run the Rocks is the only race permitted in the legendary Red Rocks Park & Amphitheatre. Over 1,500 participants will enjoy live music along the route, party with […]
Indian Creek Fifties
The Indian Creek Fifties takes advantage of the challenging and little used terrain just southwest of the Denver Metro area. Loop 1 climbs to 8000′, and quickly flows down into the Grand Valley for a few gorgeous pink sunrise soaked miles. This loop almost seems friendly, until you’re given a few sharp stabs in the […]
Bobcat Trail Races
Bobcat Trail Race was created to feature one of Colorado Spring’s best city parks, Palmer Park. Runners will enjoy views of the city and Pikes Peak from the rocky bluffs. Come out and enjoy this amazing trail system, right in the heart of the city! Formerly a Mad Moose Event & graciously passed on to […]
Blue Sky Trail Marathon
Taking place on the trails between Horsetooth Mountain Park and the Devil’s Backbone Open Space, the Blue Sky courses take you on a north-south tour of the easternmost hogbacks of Northern Colorado’s Front Range mountains. With a moderate amount of elevation gain and loss and a variety of terrain, the route offers a little bit […]
Living Water 5K
5K Fun Run race and family friendly 1mile run/walk to help support communities who are in dire need of clean, sustainable water solutions and those suffering from recent disasters. The event will be held at the lovely Berkeley Lake park (across from Lakeside Amusement park), and will be a timed, point to point race following […]
Sean May Memorial Run
The run/walk is held to honor Sean May, a Chief Deputy District Attorney with the 17th Judicial District Attorney’s Office who was murdered in his backyard in 2008 when he was returning home from work. During his seven years of service in Adams County, May served in a variety of assignments, including a rotation in […]
Great Trailhead Foot Race
Welcome to the Great Trailhead Foot Race at Bear Creek Lake Park! Featuring legitimate TRAILS in the shadow of Denver's skyline, you'll love the single-track and dirt as you race 5 miles, or a double lap of 10 miles to the finish line party!
Canyonlands Ultra
Canyonlands 100K, 50 Mile, 50K, Marathon, Half Marathon, and 15K Canyonlands Ultra starts and finishes at the Behind the Rocks Trail, along the border of the Behind the Rocks Wilderness Study Area. Moab's last hidden gem; its tall standing Navajo Sandstone domes and fins can be seen from many places along the course. From smooth double […]
Bridge Runner Ultra
Discover the scenic 35-mile loop starting in Canon City, Colorado, tracing along the Arkansas River and through historic Tunnel Drive tunnels. Ascend to 7,109 feet for panoramic views of Royal Gorge and Pikes Peak. Runners navigate pristine singletrack in Royal Gorge Mountain Park, cross the highest US bridge, and descend through Temple Canyon. With only […]
Race to Cure Sarcoma 5K
The Race to Cure Sarcoma (RTCS) is the premier run/walk series in the United States, focused on raising awareness, providing education, and research funds for sarcoma. Each year, the Sarcoma Foundation of America (SFA) hosts more than (20) RTCS events across the country. We provide a unique space in the sarcoma community where patients, survivors, their friends, […]
MonsterDASH
Colorado's Favorite Halloween Runs....Each year the Theme Changes!! This festival on Sloan's Lake, brings scary music, tons of Blow Ups, Carnival Games and Scary Clowns. The 5k and 10k run loops around beautiful Sloan's Lake and finishes in the CIRCUS Expo....with Games, Hot Dogs, Pop Corn and Balloons. The Race starts at 9:30am for the […]
Hoofin’ It Through the Hollows 5K
deKoevend Park 6315 S. University Blvd., Centennial, CO, United StatesRunners of all ages and abilities, families, and dogs are all welcome to join us for this Halloween celebration! Dress in your Halloween best for a chance to win prizes at the pre-race the costume contest before the race at 5 pm.
Beware the Bear Trail Races
Run the original Bear Creek Lake Park trail race - the Beware the Bear Trail Races - on October 17th. This trail race consists of a 14.2K or a 5K. Or do them both with the double! There is also a kids 1K.
Odyssey Odyssey 5K
The Odyssey Odyssey Fun Run is entering its 9th year. It has always been centered around having fun and exercising our bodies. It is an all-inclusive event, which is why all the races are FREE to participate in. We will be accepting donations for entrance fees but that is not a requirement for participation. The […]
MonsterDASH
Colorado's Longest running Halloween race....since 2006, we have changed the THEME to this race year after year! We wil have scary music and a CIRCUS Themes Expo at the start/finish. Hired Clowns on site and a circus atmosphere with Games, Hot Dogs, Pop Corn and Drinks. Stay for the Party and have a fun time. […]
Narrowleaf Lake Run
Brisk autumn running in Colorado – OH YEA! Join us for a family fun event with three distance options at the beautiful Boyd Lake State Park venue. What’s a “Narrowleaf” you ask? The Narrowleaf Cottonwood Trees are the most densely populated tree species at Boyd Lake State park. We thought the name was fitting and […]
Spooky Sprint Half Marathon
Join us for the annual Spooky Sprint 5k/10k & Half Marathon! A fun, Halloween-themed event that is perfect for the whole family.
Colorado 24 Hour Run
Welcome to the Colorado 24 Hour Run! We aim to provide a fun, welcoming race experience that allows everyone to find a challenge, no matter where you’re at on your running journey. Want to see how far you can go in 6, 12 or 24 hours? Or achieve a new furthest distance? What about setting […]
Foundry Halloween 5K
Soda Creek Elementary School 220 Park Avenue, Steamboat Springs, CO, United StatesA relatively new event to close out the Steamboat Springs Running Series season, bringing people of all ages together to celebrate Halloween in a safe, sober and fun way. The Foundry Treatment Center provides an opportunity for lasting recovery through an integrative body, mind and spirit treatment program. Comfortably located in the majestic Rocky Mountains […]
I Ain’t Scared (of 5K)
Dress up and run spooky and silly at the I Ain't Scared (of 5k) in Thornton! Fun music, Halloween snacks and costumes galore!! This event only comes around once every few years when Halloween lands on a weekend. You don't want to miss it! Every racer gets a T-shirt with GLOW IN THE DARK printing […]
EAPL Zombie Run 5K
Run, walk, crawl family event supporting the Evergreen Animal Protective League (EAPL). Bring your family (doggies are welcome)! We strongly encourage your spookiest, ghoulish, Halloween gear! Come out and HOWL with EAPL. The race is set in the mountains West of Denver, the course begins and ends at Buchanan Rec Center Ball Fields. The course […]
Rim Rock Marathon
Join the Grand Junction Sports Commission for a monumental run on Sunday, November 5th, 2023! Rim Rock is the only marathon and half marathon that runs through the Colorado National Monument in beautiful Fruita, Colorado. The race course gives runners amazing views of the Grand Valley and finishes at the Fruita Community Center.
RMRR Prairie Gateway Park 15K/5K
Prairie Gateway Park Prairie Parkway, Commerce City, 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 goal to shoot for whatever your speed. Just show up an hour before the start and we’ll get you ready for your race. It’s an […]
All-Out Kooky-Spooky
From the base of Table Mountain and Colorado's spectacular foothills, All-Out Multicourse presents Kooky-Spooky from Jefferson County's NAAC Stadium… easily accessible from several nearby highways. Along with its Endless Series sidekick in March, Spring Fever, these 5K, 10K & Half Marathon courses will hug the shores of Arvada's Blunn Reservoir via the Ralston Creek Trail and will […]
Kessel Run Ultra
Located in Fruita, Colorado, just a quick drive from the Front Range, this is the ultimate Racecation Adventure!! Enjoy sweeping views of the San Juan Mountains and the Colorado National Monument as you run through the high desert. All distances begin on fast, flowing singletrack and work their way back to the steep ups and downs […]
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace 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 […]
Canceled Marathon At The MAC
This scenic race will feature three distances: a Marathon, Half Marathon, and 5K, offering something for runners of all abilities. Participants will experience beautiful single-track trails, rolling terrain, and sweeping views of the surrounding Castle Rock landscape. The park’s extensive trail network winds through valleys, hills, and natural open space, creating a fun and challenging […]
Moab Trail Marathon
We are happy to announce that we will again be running Sundays 1/2 Marathon in addition to the traditional Saturday Races. So, you may run the 1/2 marathon on either Saturday or Sunday (same course, same support, but two separate awards.) If you want to run the Marathon, 10K or Kids K- they will be […]
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