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

  • Highlands Ranch Race Series

    HRCA Oktoberfest 5K

    Highlands Ranch Town Center 9352 Dorchester St., Highlands Ranch, CO, United States

    Put on your lederhosen and sneakers as we kick-start the annual Highlands Ranch Community Association's Oktoberfest event in Town Center with the Oktoberfest 5K! This course is a mixture of both sidewalk and gravel trails and is well-suited for all ability levels. After the race, plan to stick around for all-you-can-eat pancakes from Flippin Flapjacks', […]

  • Emerald Mountain Trail Run

    Howelson Hill Steamboat Springs, CO, United States

    This races offers two distances on Emerald Mountain, 12k (ends up being closer to 7.75 miles long) and a 4 mile run. This scenic course will begin at the base of Howelsen Hill and tour Emerald Mountain through aspen lined single track. Hikers are welcomed in the 12k. This race is a fundraiser for Northwest […]

  • Colorado Brain Tumor 5K

    Sloan's Lake Park 1700 Utica Street, Denver, CO, United States

    The Colorado brain tumor community will come together for a 5K Walk/Run to raise awareness and funds to support the needs of patients with brain tumors and their families.

  • Science Stride 5K

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

    The Friends of the National Center Science Stride 5k brings together our community for a common cause: Inspiring the next generation of scientists! This event provides an excellent opportunity for everyone who believes in the importance of STEM education to come together and support Friends of the National Center. Runners and walkers of all abilities […]

    $50
  • Colorado Brewery Running Series

    Oktoberfest 5K

    Prost Brewing Company 2540 19th St, Denver, CO, United States

    Join us for The Oktoberfest 5k at Prost Brewing on September 27, 2025, for a 5k-ish, fun run event that starts and ends at this awesome taproom in Northglenn. Run, walk, jog - whatever goes! Complete the course and celebrate with us and a FREE, local craft brew at the finish line. Start windows will […]

  • Canceled Rising Phoenix 5K

    Sylvan Dale Guest Ranch 2939 N CR 31D, Loveland, CO, United States

    The Rising Phoenix Festival & 5K Run/Walk for Suicide Prevention is Combat Recovery Foundation's first community awareness event. Runners, walkers, dogs and participants of all ages, volunteers, and spectators will gather together in celebration of life. The 5K provides an important sense of community for suicide loss and trauma survivors and creates a space for […]

  • Lederhosen Run

    The Tavern at Red Feather Lakes 1078 Ramona Dr, Red Feather Lakes, CO, United States

    The Tavern at Red Feather Lakes is planning this year's Oktoberfest on Saturday, September 27th. As a part of the festivities, Caring Hearts of Red Feather Lakes Foundation is putting on our annual Lederhosen Race! The race begins at 1pm. The race starts and ends at The Tavern at Red Feather Lakes. The Oktoberfest expo […]

    $35
  • Sawatch Ascent 50K

    County Road 321 Nathrop, CO, United States

    Built to showcase the stunning beauty of the Sawatch Range, this high alpine and vert-heavy 50K will challenge and inspire you in equal measure! From starting under the shadow of Mount Princeton and the endless miles of buttery, aspen shaded Colorado Trail singletrack, to the awe-inspiring high point of 13,150ft and panoramic views of Colorado’s highest range, you will get to experience the wonders of the Sawatch over 33 miles and 7,000ft of vertical gain.

  • Boulderthon

    Pearl Street Mall 11th and Pearl St, Boulder, CO, United States

    Run one of the fastest-growing, top-rated marathons in the country! After nearly tripling in size and selling out last year, Boulderthon has instituted a new 5,000 runner cap and is expected to sell out again this year. Run a 5k, 10k, Half, or Full, at the foothills of the Rockies, in the stunning running mecca […]

  • Last Call Triathlon

    Boyd Lake State Park 3720 N Co Rd 11C, Loveland, CO, United States

    Yes! I want ONE MORE adventure!! Escape to the lake! The Last Call Triathlon will be an event you’ll look forward to all season long. Why? Beautiful mountain views, great weather and a family fun venue! Did we mention camping? Yup! There’s that too. Sitting on the east side of Loveland and southeast of Fort Collins, […]

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