Event details subject to change. Please confirm all information via event website.

  • Pagosa Duathlon

    Turkey Springs area Cnr Turkey Springs & Monument Rds, Pagosa Springs, CO, United States

    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.

    $45
  • CMRA Elk Meadow Trail Run

    Elk Meadow Park 2855 Bergen Peak Drive, Evergreen, CO, United States

    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

    Crested Butte Nordic Center 620 2nd St, Crested Butte, CO, United States

    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 […]

  • Heatwave Half Marathon

    Goose Gossege Park 3950 Mark Dabling Blvd, Colorado Springs, CO, United States

    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

    Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

    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 […]

  • High Lonesome 100

    County Road 321 Nathrop, CO, United States

    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

    Fellin Park 1001 US-550, Ouray, CO, United States

    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

    Aspen Mountain 601 East Dean Street, Aspen, CO, United States

    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 […]

  • Silverton Alpine Marathon

    Memorial Park - Silverton 1800 Greene St, Silverton, CO, United States

    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

    H2O'Brien Pool 10795 Victorian Dr, Parker, CO, United States

    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

    Carter Lake 971 N County Rd 31, Berthoud, CO, United States

    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

    Goose Gossege Park 3950 Mark Dabling Blvd, Colorado Springs, CO, United States

    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

    Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

    ‘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

    Thumb Open Space 101 Peak View Drive, Estes Park, CO, United States

    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

    La Salle Community Center 101 Todd Ave, La Salle, CO, United States

    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

    Alma City Park 59 Buckskin St, Alma, CO, United States

    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

    Heritage High School 1401 W Geddes Ave, Littleton, CO, United States

    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 […]

  • Respect Life 5K

    Light of the World Catholic Church 10316 W Bowels Ave, Littleton, CO, United States

    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

    Powderhorn Mountain Resort 48338 Powderhorn rd, Mesa, CO, United States

    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 […]

    $170
  • Canceled Great Escape Trail Race

    Centennial Park - Cañon City Cañon City, CO, United States

    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

    Gypsum Sports Complex 52 Lundgren Blvd, Gypsum, CO, United States

    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

    Auraria Campus 1068 9th Street Park, Denver, CO, United States

    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 […]

    $39
  • Gastro-Dash 10K

    Roberts Lake Park 1035 N 7th St, Berthoud, CO, United States

    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

    Leadville 124 E. Sixth Street, Leadville, CO, United States

    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

    Cog Railway/Barr Trail 515 Ruxton Ave, Manitou Springs, CO, United States

    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

    Washington Park - Denver 701 S Franklin St, Denver, CO, United States

    The Donor Dash is an annual 5K that honors, celebrates, and recognizes those touched by organ and tissue donation.

    $17 – $60
  • Kendall Mountain Run

    Memorial Park - Silverton 1800 Greene St, Silverton, CO, United States

    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

    Game Check Park 970 E Idaho Springs Rd, Idaho Springs, CO, United States

    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 […]

  • Never Summer Ultra

    State Forest State Park 56750 CO-14, Gould, CO, United States

    The Never Summer 100km & 60km will take place almost entirely within the boundaries of State Forest State Park and run between the Never Summer Mountains on the northern border […]

    $175 – $440
  • Pikes Peak Ultra

    Bear Creek Regional Park 245 Bear Creek Road, Colorado Springs, CO, United States

    Pikes Peak Ultra was created in 2015 to showcase some of the very best trails in Colorado Springs.  As a teenager, RD Justin Ricks trained on these trails and dreamed […]

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