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

  • All-Out Dog Days

    Church Ranch Office Park 10170 Church Ranch Wy, Westminster, CO, United States

    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

    Siena at Brightwater 1000 Brightwater Club Drive, Gypsym, CO, United States

    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.

    $40 – $150
  • 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
  • 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 goes right back to supporting the team. New this year, all-you-can-eat pancake breakfast provided by Flippin' Flapjacks. The Liberty Bell Cross Country Invitational has been […]

  • Staunton State Park 6 Mile

    Staunton State Park 12102 S Elk Creek Rd, Pine, CO, United States

    The second of Evergreen Park and Recreation District's four-race trail series. Join us at Staunton State Park for a beautiful 6-mile trail race. Please bring a water bottle; this is a cup free race.

  • 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 Loop competition while still maintaining the traditional 15k race. This is a low swag, no frills race.

  • Race in the Clouds Dirt Festival

    Buckskin Cemetery 227 Buckskin Street, Alma, CO, United States

    Get ready for a day of exciting outdoor activities at 10,600 feet in beautiful Alma, Colorado! Our dirt festival has something for everyone: mountain bike racing, trail running, a free kids' bike race, an OFF-Road Duathlon (Run + Bike) and camping in a stunning meadow surrounded by 14,000-foot mountain peaks. What are the courses like?? […]

  • NoCo All-Comers Track Meet #3

    Loveland High School 920 West 29th St., Loveland, CO, United States

    This is the third in a series of four track meets in Northern Colorado during the summer of 2025. The meet will take place at Loveland High School and features a variety of track events including: 8:00 am: Elite Women's 1 Mile Run 8:20 am: 1 Mile Run 8:40 am: Kids 50m Dash 9:00 am: […]

  • 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.

  • Aspen Valley Marathon

    Lions Park 101 Midland Ave, Basalt, CO, United States

    Mark your calendars – Don’t miss out on this exhilarating race through the stunning landscapes of Aspen, Colorado! Join us for a one-of-a-kind experience that you’ll cherish forever. The Aspen Valley Marathon takes place in the heart of the Rocky Mountains. The marathon is a Boston Marathon qualifier, offering runners the opportunity to qualify for […]

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