Event details subject to change. Please confirm all information via event website.
Week of Events
1876 Centennial Run
Join us for the 1876 Centennial Run (3.76k/5k/10k/18.76k Challenge), at the New Belgium Ranger Station in Snowmass on August 7 & 8, 2026 In honor of the State of Colorado's 150th Birthday this August, join us for the 1876 Centennial Run (3.76k + 5k + 10k + 18.76k Challenge) on August 7 & 8, 2026. […]
Ute 100
The Ute 100 is the highest and most scenic race in Utah, taking runners on a breathtaking tour of the La Sal Mountains, Utah's second highest mountain range. The 100 mile course has an average elevation over 8,700 ft and boasts roughly 23,000 ft gain.
Emerald Mountain Epic
The Emerald Mountain Epic presented by Hard Headed attracts some of the nation's best mountain bike and trail running racers, while still offering incredible opportunities for athletes of all skill levels to test their meddle. Our race is a uniquely rewarding and challenging experience in that it is 90% singletrack with major elevation gains. To […]
Sunday, August 2, 2026
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August 2, 2026 -Stagecoach Gravel Triathlon
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August 2, 2026Bound for Boston Marathon
Stagecoach Gravel Triathlon
We didn't get the chance to launch this race in 2020, but that didn't diminish our passion for this brand new style of triathlon! To say this race is “unique” would be an understatement! Limited to just 250 athletes, we're excited to announce the first ever gravel triathlon to the Colorado triathlon landscape! This event […]
Bound for Boston Marathon
Have you been dreaming of running Boston? Need to shave a few minutes off your time to qualify? Looking for the perfect course to set a PR? Regardless, if you want to run Boston or not, THIS is the event for you! We're racing around Northfield High School, and the course is a 1-mile super […]
Monday, August 3, 2026
No events on this day.
Tuesday, August 4, 2026
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August 4, 2026 -Eltuck Valley 5K
Eltuck Valley 5K
Join us each Tuesday evening in August for a fun series of shorter midweek trail races. Our goal is to offer a fun, low-key series of races designed to give newer trail runners an opportunity to dip their toes into the trail racing waters, and to offer more experienced trail racers a chance to sharpen […]
Wednesday, August 5, 2026
No events on this day.
Thursday, August 6, 2026
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August 6, 2026Eldorado Springs Run for the Cure
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August 6, 2026Boulder Stroke & Stride IX
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August 6, 2026 -BRR Summer Track Series #5
Eldorado Springs Run for the Cure
Founded in 1979, the Eldorado Run for the Cure is the longest operating charitable footrace in the State of Colorado. All proceeds from the annual four-mile run benefit the Colorado Cancer Foundation's life-saving work, from funding oncology research at the University of Colorado's (CU) Division of Medical Oncology to aiding patients at the CU Hospital […]
Boulder Stroke & Stride IX
The Boulder Stroke & Stride offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-Lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the reservoir dam. Stroke & Stride happens weekly on Thursday nights throughout the Summer from June 4th to August 6th WITH THE EXCEPTION OF Thursday June […]
BRR Summer Track Series #5
Join the Boulder Road Runners as we host the premier track and field meet series in Colorado! Tradition runs deep with this legacy event. Now in its 4th decade, the meets welcome people of all ages and abilities – youth, masters, elites, and age-groupers alike. Heats are organized by predicted finish time, giving everyone peers to […]
Friday, August 7, 2026
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August 7, 2026 -High Five 100
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August 7, 2026 -Jane Welzel Mountain Avenue Mile
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August 7, 2026First Fridays 5K
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August 7, 2026 -CMRA/RMRR 5K
High Five 100
In 2018 local ultra runners of Lake City came together to create a challenge meant to shake even the most elite runners to their core. What we came up with is the High Five 100. To complete this challenge, you must begin in Lake City and make your way on foot to 24 specified locations, consisting […]
Jane Welzel Mountain Avenue Mile
What is better than one day of running? TWO days of running! The Choice City Running Event on August 5th and 6th at Civic Center Park in Fort Collins has something for everyone. Kick off a weekend with the Jane Welzel Mountain Avenue Mile on Friday evening! Continue running strong the following day with the Human Race Half Marathon, 10K, and 5K. The party continues both days in the park with live music, vendors and a New Belgium beer garden!
First Fridays 5K
Friday nights in the summer are made for spending time close to home, enjoying the beautiful weather, and unwinding from the long week. Why go anywhere else but Downtown Castle Rock? Start the night off on the right foot with the First Fridays 5K. Before enjoying the free concert event, get a workout with the […]
CMRA/RMRR 5K
Join us for the August Trophy Series race and picnic at deKoevend Park in Centennial. This year our friends with the Colorado Masters will be joining us again for a great race and a fun post-race picnic!! We will be providing soda, seltzer, and chips. We ask that you bring your own picnic fare. We […]
Saturday, August 8, 2026
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August 8, 2026 -Georgetown to Idaho Springs Half Marathon
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August 8, 2026 -All-Out Runapalozza
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August 8, 2026 -Reece’s Roundup 5K/10K
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August 8, 2026 -Human Race Half Marathon
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August 8, 2026 -Summer Sizzler 5K
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Featured August 8, 2026 -Featured Run the Rockies Trail Half Marathon
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Featured August 8, 2026 -Featured Arapahoe Warrior 5K
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August 8, 2026 -Dog Days of Summer 5K
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August 8, 2026 -HRCA Splash Mash Dash Kid’s Triathlon
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August 8, 2026 -Strides For Change
Georgetown to Idaho Springs Half Marathon
Part of the Colorado Mountain Half + Series, Georgetown to Idaho Springs Half Marathon is a Colorado Runner’s Must-Do. This iconic Half Marathon is one of the most pleasurable races in the western US. The point-to-point course is a scenic and gently rolling downhill mountain course that winds down the Clear Creek Valley -- starting at an […]
All-Out Runapalozza
As those summer mornings are just beginning to cool, join us for a celebration to end the season and our 11th Annual Runapalooza! From the award winning Apex Center, these 5K, 10K & Half Marathon courses will run west along the 2020 Best of the Best Ralston Creek Trail through Arvada's open spaces and stunning golf […]
Reece’s Roundup 5K/10K
Join the Rubino Family at Philip S Miller Park in Castle Rock for the Annual Reece’s Roundup 5K/10K. This event supports Reece Rubino in his fight against Spinal Muscular Atrophy.
Human Race Half Marathon
What is better than one day of running? TWO days of running! The Choice City Running Event in Civic Center Park Fort Collins has something for everyone. Kick off a run-filled weekend with the Jane Welzel Mountain Avenue Mile on Friday evening with 1-mile races for everyone including kids, middle & high school students, families, […]
Summer Sizzler 5K
Join us for the annual Summer Sizzler! Whether you are looking to run, walk or just enjoy the race SWAG this race is a sure thing for a great time and an incredible experience! This is a fun, family event for all ages with all distances! Great Swag - designer shirt & custom medal Chip-timing […]
Run the Rockies Trail Half Marathon
The Run the Rockies Trail 5k, 10k, and half marathon will lead runners through the Frisco Peninsula trails with breathtaking views of Dillon Reservoir and the Ten Mile Range. This is a great course for a first time half-marathoner or runners looking for a fun course that offers single track and dirt road trails. Racers […]
Arapahoe Warrior 5K
Come out and support the Arapahoe Warrior Cross Country team at the 3rd annual Arapahoe Warrior 5K. $10.00 of every registration goes directly back to the Arapahoe Cross Country Booster team.
Dog Days of Summer 5K
Come join us for a race around the entirety of beautiful Lake McIntosh! This 3.5 mile race is a half paved/half dirt course surrounded by wonderful mountain views, vast farmlands, and beautiful aquatic wildlife! Gather at Dawson Neighborhood park near the pirate ship playground where you will find an assortment of vendors, music, games, and […]
HRCA Splash Mash Dash Kid’s Triathlon
The Splash Mash Dash Kids Triathlon is the perfect for kiddos looking for a way to "TRI" the sport of triathlon or tune up their skills for a larger race. The race will offer kids a safe and fun environment for racing. To encourage participation and enjoyment for all, The Splash Mash Dash Kids Triathlon […]
Strides For Change
Join us on August 8th, 2025 at Sloan’s Lake for Strides for Change – a 5K for Youth Mental Health, presented by Resolute Counseling Center. This community-centered event is more than a race — it’s a movement to support and uplift the mental health of our youth. Hosted by Resolute Counseling Center, whose mission is to […]
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