Event details subject to change. Please confirm all information via event website.
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 […]
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 […]
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 […]
Heritage Eagles 5K
Support the Heritage Eagles cross country team at the annual Heritage Eagles 5K. Last year's race, raised over $3,500 for the Heritage Eagles xc team; $ 10.00 of every registration […]
10K and 5K @10,000 Feet
Vail Mountain's Views Won't be the Only Thing Taking Your Breath Away! The 10@10 returns to its original route on Grand Traverse. The race starts 10,000 feet above sea level, on the […]
Spring Creek Memorial Trail Run
Spring Creek Trailhead Steamboat Springs, CO, United StatesThis race is held in memory of Patty Brenner Hagberg who was struck and killed by a truck along the lower part of the trail in 1991. This race should […]
Respect Life 5K
The race is the same as last year, including the new course (the path was repaved and widened!). You can participate as a runner, walker, donator, or volunteer. 5K runners […]
Powderhorn Mountain Trail Climb
Beat the heat with the Grand Junction Sports Commission’s Powderhorn Mountain Trail Climb. Trek up the Stagecoach Trail, take in the beauty of the Grand Mesa and Grand Valley. The […]
Canceled Great Escape Trail Race
The Annual Royal Gorge Whitewater Festival (RGWF) features whitewater competitions and land-based recreation events to celebrate the whitewater season on the Arkansas River. Enjoy summer flows in a fantastic whitewater […]
Gypsum Daze 5K
The Gypsum Daze 5K Run/Walk is a tradition in Gypsum-32 years strong. Serious runners can go for a PR, but we invite everyone to head out for some exercise and […]
OCA Panda Run 5K
Come join Organization of Chinese Americans' Charity 5K Panda Run or OCA 1K panda walk on Saturday 7/18/2026 at 9 am at MSU - Regency Athletic Complex. Stay after the […]
WeldWerks Brewing 5K
Weldwerks Brewing Co 508 8th Ave., Greeley, CO, United StatesJoin us for the WeldWerks Brewing 5k & 10k on July 18, 2026. This fun run event starts and ends at this awesome taproom in Greeley. Run, walk, jog - […]
Gastro-Dash 10K
The Berthoud Gastro-Dash 10K is not just a footrace; it’s an epic, hilarious test of both speed and stomach, challenging runners to tackle a 6.2-mile course punctuated by mandatory food […]
TransRockies Run
The TransRockies Run (Pass to Pub) is a trail running stage race also known as “Summer Camp for Big Kids”! A three stage race traversing the continental divide between Hope […]
Barr Trail Mountain Race
The Barr Trail Mountain Race is one of the Front Range’s historic summer mountain running events. The 12.6-mile course begins at the Cog Railway Station (6,570 ft) in Manitou Springs, Colorado, ascends […]
Donor Dash
The Donor Dash is an annual 5K that honors, celebrates, and recognizes those touched by organ and tissue donation.
Kendall Mountain Run
Meet the mountain this summer in Silverton, Colorado! The Kendall Mountain Run starts in downtown Silverton and traverses jeep roads to within a final 300 vertical foot scramble to the […]
Floyd Hill Dash
Calling all adventurers and nature lovers! It's time to cool down, head to Idaho Springs for the Floyd Hill Dash 5k! Picture yourself surrounded by breathtaking mountain views, crisp fresh […]
BRR Summer Track Series #4
Potts Field 4001 Discovery Drive, Boulder, CO, United StatesJoin 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 […]
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