Event details subject to change. Please confirm all information via event website.
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 […]
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 […]
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 […]
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 […]
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 […]
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 […]
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. […]
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 […]
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 […]
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 […]
Odell Brewing 5K
Odell Brewing Company 800 East Lincoln Avenue, Fort Collins, CO, United StatesJoin us for the Odell Brewing 5k, and great, local craft beer at Odell Brewing Company in Fort Collins on July 11, 2026 Join us for The Odell Brewing 5k […]
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 […]
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 […]
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 […]
Mountain Goat Kids’ Trail Running Series #3
Frisco Adventure Park 621 Recreation Way, Frisco, CO, United StatesFor the nineth year, the Town of Frisco is hosting a series of four kids’ trail running races over the summer. The entire family is welcome to come out for […]
Summit Trail Running Series III
Blair Witch Trailhead - Horseshoe Gulch 2700 Tiger Rd, Breckenridge, CO, United StatesExplore the trails of Breckenridge this summer with the 23rd annual Summit Trail Running Series with each race followed by a post-race party! The Series consists of 5 trail races […]
Boulder Stroke & Stride VI
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe 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 […]
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") […]
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 […]
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 […]
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 […]
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 […]
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 […]
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 […]
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 […]
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 […]
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