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 mountains, from arid forest to alpine tundra peaking out over 12,000 foot above sea level 4 times. You will enjoy golden aspen leaf covered trails […]

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 back at the Boulder Taco Fest, ready to celebrate your run at Boulder’s favorite summer festival. How Much? The entry fee is $50 and it […]

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 hit the scenic trails of Standley Lake under the stars. With a mix of packed dirt trails, single-track, and a hint of bike path, this […]

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.

$35.00

Flat and Fast Eltuck Valley 12K

Lory State Park 708 Lodgepole Dr, Bellvue, CO, United States

Join us each Tuesday evening in August for a fun series of shorter midweek trail races. Our goal is to offer a fun, low-key series of races designed to give newer trail runners an opportunity to dip their toes into the trail racing waters, and to offer more experienced trail racers a chance to sharpen […]

$25

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 […]

American Heroes Run

Rogers Grove Park 220 North 95th Street, Longmont, CO, United States

The tragic events of 9/11/01 changed our nation forever. Let us not forget our proud history and those who fight everyday to keep us free. Please join us for this special day on this beautiful, flat, fast 1.05-mile loop course. The 100-mile race cutoff is 30 hours. No politics, just patriotism. - David Clark #WeAreSuperman […]

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