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

  • Rock Hawk Trail Race

    Phillip S. Miller Park 1375 West Plum Creek Pkwy, Castle Rock, CO, United States

    Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak up the amazing views. This is an excellent race for both first-time and veteran trail runners, and provides a nice test for those who are […]

  • Boulder Sunset Triathlon

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

    Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local favorite. For the 5th year in a row we are the proud host of the Mountain Collegiate Conference race and the USAT Duathlon Race Series. […]

  • Boulder Sunset 5K/10K

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

    The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, and start training for the end-of-the-summer endurance festival with BBSC.

  • South Suburban Race Series

    Bluffs 8K Trail Run

    Prairie Sky Park 10249 Ridgegate Circle, Lone Tree, CO, United States

    The Bluffs 8K Trail Race has rolling hills and beautiful views as you run or walk through the Bluffs Regional Park. The race will start/finish near the Prairie Sky parking lot o n August 28th.

  • Grand Traverse Mountain Run

    Mt. Crested Butte Mt. Crested Butte Ski Resort, Crested Butte, CO, United States

    The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, runners travel 40 miles across the Elk Mountains with over 6,000′ of elevation gain.

  • 10K (and 5K) @ 10,000 Feet

    Rabbit Ears Pass Steamboat Springs, CO, United States

    This is a challenging trail run with beautiful terrain and breathtaking scenery. The 10K race begins at 10,000 ft at the summit of Rabbit Ears Pass. The course begins by heading uphill on USFS dirt roads and 2 track, and then then heads downhill on single-track, ending on a cross country single-track. The total elevation […]

  • Oak Creek No Fun Run

    Oak Creek Town Hall 123 Nancy Crawford Blvd, Oak Creek, CO, United States

    The Running Series is excited to have the Oak Creek No Fun Run on our schedule again! Please join us in remembering long-time Running Series competitor Larry Brooks, a former organizer of the Oak Creek No Fun Run. This 5K run will take you through the streets of Oak Creek, looping through the scenic Oak […]

  • Littlefoot Sprint Triathlon

    Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United States

    Enjoy a fun late season tri at beautiful Bear Creek Lake Park in a land before time. Set at the base of the foothills, the Littlefoot Triathlon starts off with a 750 meter swim in Big Soda Lake, with water temps expected to be approximately 70 degrees. Next, a rolling 15K bike ride on smooth […]

  • CMRA South Seven

    Bluffs Regional Park 10099 Crooked Stick Pl, Lone Tree, CO, United States

    The course will be on wide, crushed gravel paths and, depending on the status of construction in the nearby neighborhood, potentially a little bit of single track. It's a hilly, but very run-able course, a few ups and downs during this 7 mile course! We'll travel "the wrong way" around the standard Bluffs route before […]

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