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, […]

Thirsty 13 Half Marahton

Ska Brewing Durango, CO, United States

It's a race.  It's a Brewfest.  It's the Thirsty 13 Half Marathon! Are you thirsty for gorgeous scenery?  You won't find a course more beautiful than this one.  With the […]

Rio Grande 100

Brown Memorial Park 86 County Road 15, South Fork, CO, United States

The Rio Grande 100 starts and finishes on the banks of the mighty Rio Grande River in beautiful South Fork, Colorado. The race takes you though the amazing La Garita […]

Boulder Taco Run

Boulder International Peace Garden 1777 Broadway, Boulder, CO, United States

We’ve put together a non-competitive fun run on some of Boulder’s most beautiful multi-use paths. There’s even an aid station with some Boulder Taco Fest -themed treats. You’ll finish up […]

Westminster Trail Race

Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United States

Join us at beautiful Standley Lake in Westminster for an unforgettable evening at the Westminster Night Trail! For its 12th year, this race takes on a whole new energy as runners […]

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, […]

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 […]

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 […]

Flaming Foliage Relay

Citizens Park 17th Ave & Miner St, Idaho Springs, CO, United States

Flaming Foliage is a 165 mile overnight team relay race adventure with single track trails, from Idaho Springs to beautiful Buena Vista, over Guanella, Georgia & Fremont Passes. Since 2013, […]

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