Event details subject to change. Please confirm all information via event website.
Main Avenue Mile
Celebrate 250 years of freedom with one MILE race down Durango's historic Main Avenue. Starting at Buckley Park and turning around at the train station, enjoy the opportunity to test your speed and race down a closed Main Avenue right before the parade. Race Prizes for top 3 overall Male and Female and age group […]
Canceled Gold Roots Trail Series #2
Courtney Ryley Cooper Park 2350 Colorado Blvd, Idaho Springs, CO, United StatesRun the Mighty ARGO hill this summer in a 4 race series! You will have the option of a short loop (~5 miles, ~750' gain) or a long loop (~9 miles, ~1400' gain). Both loops climb the Rosa Gulch trail and come down Virginia Canyon. Start and end in Courtney Ryley Cooper Park. Routes subject […]
Silverheels Trail Runs
**BIG CHANGES TO SILVERHEELS** HPRS continues to work in earnest on a newly revamped Silverheels Trail Runs experience. Traditionally the Silverheels 100-Mile was held in concert with The Last Call Fifties, and on the same weekend. We made the decision to move on from the “Last Call” name except for it’s attribution to the 50-Mile. […]
Hardrock 100 Endurance Run
About The Run The Hardrock Hundred Mile Endurance Run is an ultramarathon of 100.5 miles in length, plus 33,050 feet of climb and 33,050 feet of descent for a total elevation change of 66,100 feet, at an average elevation of over 11,000 feet. The run is held on a loop course on 4WD roads, dirt […]
Frisco Duathlon
Are you looking for a fun, single track trail challenge this summer? Register for the Frisco Duathlon taking place on Friday, July 10, 2026. The Duathlon will feature trail running and mountain biking on the Frisco Peninsula trails and is open to all ability levels.
Canceled Silver Rush 50 Mile
Leadville 124 E. Sixth Street, Leadville, CO, United StatesTake on 50 miles of extreme territory that starts at 10,200 feet and reaches 12,000 feet on four separate occasions at the Silver Rush 50 Run. It will leave your lungs burning, heart pounding and eyes completely amazed — while also preparing you for the pinnacle Leadville Trail 100 Run presented by La Sportiva. New […]
All-Out Dog Days
Get ready for some fun in the sun and a great mid-season test of your training as we bring our 11th Annual Dog Days 5K, 10K & Half Marathon! Centrally located between Denver & Boulder along with its Endless Series sidekick in December Fa La La, the beauty of our breathtaking Flatirons as a backdrop will inspire you […]
LG Triathlon
Can you keep a secret? Eagle, Colorado, is a special place, and they have a fantastic triathlon that you should not miss. They're calling for triathlon experts, newbies, and everyone in between, including the kids! Join them on July 9th for the 14th Annual LG Tri, a sprint triathlon held in the beautiful Vail Valley town of Eagle.
Heatwave Half Marathon
5K/10K/Half- Marathon & Relay registration includes a custom bib, designer shirt, and a custom finisher medal! 1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher medal! The kid's dash is a fun, untimed dash for our kiddos ages 10 and under. Registration includes a mini bib, youth-sized shirt, […]
Pagosa Duathlon
The venue of the San Juan National Forest could not be more perfect for the Pagosa Duathlon as athletes trek through aspen groves, grassy fields, and the dreaded rocky Piedra Stock driveway. Join Rise Above Violence on July 10th in Pagosa Springs for this annual event.
Cookie Chase 5K
The Cookie Chase is Denver’s race that ends with cookies. Runners and walkers can take advantage of a flat and fast course, and then enjoy fresh cookies at the finish. Our mission is to bring people together to have a fun, fit morning, all while supporting the many different needs throughout our region. All finishers […]
CMRA Elk Meadow Trail Run
Come up to scenic Elk Meadow Open Space for an exhilarating 5.1 mile trail run. This is a timed event that starts and ends near the Lewis Ridge Trail Head.
Grin & Bear It Trail Race
The Grin & Bear It is Crested Butte’s oldest trail challenge. Historically presented as a sprint to Green Lake and back, this classic event has evolved to offer a 25k Loop competition while still maintaining the traditional 15k race. This is a low swag, no frills race.
Vitality Walk
Memorial Park - Durango 2901 E. 3rd Ave, Durango, CO, United StatesYour participation in Vitality Walk helps Parkinson Association of the Rockies (PAR) push boundaries and invest in programs and services that are a lifeline to those with Parkinson’s, their Care Partners, and their families. 100% of the proceeds stay in communities throughout Colorado and Wyoming to help us provide free services, including: assessments, 50+ support […]
Vitality Walk
Logan County Courthouse 315 Main St, Sterling, CO, United StatesYour participation in Vitality Walk helps Parkinson Association of the Rockies (PAR) push boundaries and invest in programs and services that are a lifeline to those with Parkinson’s, their Care Partners, and their families. 100% of the proceeds stay in communities throughout Colorado and Wyoming to help us provide free services, including: assessments, 50+ support […]
Heatwave Half Marathon
5K/10K/Half- Marathon & Relay registration includes a custom bib, designer shirt, and a custom finisher medal! 1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher medal! The kid's dash is a fun, untimed dash for our kiddos ages 10 and under. Registration includes a mini bib, youth-sized shirt, […]
Boulder Peak Triathlon
The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons. For the veteran or first time racer, this is THE can’t miss event of the summer triathlon season, and the crown jewel of the Colorado Triathlon Series. Racers are tackling the infamous “Olde Stage” Hill, […]
RMRR Stone House 2M
Stone House Park 2800 S. Estes St., Lakewood, 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 […]
High Lonesome 100
The High Lonesome 100 is a high flying endurance race in the Sawatch range of the Colorado Rocky Mountains. With 22,500' of vertical gain and reaching an elevation of 13,150', it's a hell of a course. The race runs in a loop through some of the most beautiful single track in the state, and takes runners on the Continental Divide and Colorado Trail, through 2 ghost towns, over 5 alpine passes, through remote basins, and over soaring ridges. This year's event takes place on July 30th.
Canceled Ouray 100
With ~42k feet of gain for the 100 miler, this will be one of the most difficult things you ever attempt. Lucky for you, Ouray (dubbed the "Switzerland of America") is also one of the most beautiful places in the world. Situated in the rugged and stunning San Juan Mountain range in southwest Colorado, your […]
Audi Power of Four Trail Race
The Audi Power of Four Race Series is a premier endurance race series utilizing the unique and amazing terrain of each of the four Aspen Snowmass mountains. Each race is designed to test the limits and skills of both elite and recreational athletes. The event’s signature race is a challenging 50K Ultra is part of […]
Summer Splash Prairie Dog Half Marathon
Castle View High School 5254 N. Meadows Dr., Castle Rock, CO, United StatesWelcome to the Summer Splash Prairie Dog Half, 10k & 5k in Castle Rock, Colorado. Part of the Prairie Dog Half race series, join us in July as we race through Castle Rock along the East Plum Creek Trail.
Silverton Alpine Marathon
Experience the best of the San Juan Mountains with an 8 miler, a marathon, or a 50 kilometer run along the Alpine Loop past the historic mining ghost towns of Howardsville, Eureka, Animas Forks & Gladstone. High point is 12,930 ft atop California Pass. Low point is Silverton at 9,318ft. Total vertical gain is 3,800 […]
Kids’ TRY-athlon
This event is all about fun over competition. Boys and girls of all ability levels show their skills in three events: swimming, biking and running. Come on, kids, TRY it out! Ages: 6 to 12, based on event date Event Distances 6-7 years: 25m swim (1 length)/ 0.75 mile bike/ .5 mile run 8-10 years: 50m […]
Mountain Swim Series II
The crossing is at Carter Lake, Colorado. Situated at just below 5800 feet, this nearly 3-mile swim is located in one of the most picturesque lakes in Colorado. Cash prize awards will be given out to the top three finishers in each division. Divisions will be both non-wetsuit and wetsuit for both men and women. […]
719 Challenge 10K
The 719 Challenge run will be the official 10-kilometer (6.2 mile) run of the Rocky Mountain State Games, and, a medal event. The course will feature a mix of road and crushed gravel trails on a mostly flat, relatively fast course.
Tri Boulder
‘The Beast’ Long Course distance will be back for its second year! As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in one eventful day. Take in the natural beauty of the mountain backdrop that sets the scene for this iconic race destination. Most of the bike […]
Thumbs Up Summer Slam
Repeating 2km out-and-back laps on the Thumb Open Space trail, 540ft of vertical gain each. Start at 7:10am, finish at 7:10pm. Sunup to sundown. Collect a poker chip at the turnaround on each lap. Most chips wins. Distance awards at three milestones: 14 ascents — Estes Park 7,522' 18 ascents — Deer Mountain 10,103' 26 […]
Toni’s Trot 5K
The Town of LaSalle will host the 36th annual Toni’s Trot. This event kicks off a full day of celebration this community knows as “LaSalle Days”. Proceeds from the run will benefit the Recreation Department operating programs for all ages in LaSalle and surrounding communities.
Festival in the Clouds Firefighter 5K
Start your morning the Alma way — with a little fresh mountain air, some movement, and a big stack of pancakes. Join us for the Firefighter 5K, a laid-back community run where everyone is welcome. Bring your kids, your dog, your friends — run, jog, walk, or just saunter your way through beautiful Alma. This […]
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