MonsterDASH

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

Colorado's Favorite Halloween Runs....Each year the Theme Changes!! 2025 brings...SCARY CLOWNS / Circus Theme! Our best theme yet. Saturday Race is in Denver at 9:30am... then Sunday is in Louisville at 3:00pm on trails. This festival on Sloan's Lake, brings scary music, tons of Blow Ups, Carnival Games and Scary Clowns. The 5k and 10k […]

$35.00

BOO Run 5K

Edgewater Brewery 905 Struthers Ave, Grand Junction, CO, United States

Join this Halloween 5k fun run/walk benefiting Girls on The Run Western Colorado. Costume up and bring the family, we will haunt the town on our 5k route along the river while taking in the beautiful fall colors followed by a big costume contest!

Spooky Sprint 5K

Pueblo YMCA 3200 E. Spaulding Ave, Pueblo, CO, United States

This eerie evening race winds through a chilling course at the YMCA of Pueblo. The thrilling Halloween themed race is perfect for all ages and fitness levels. Recommended for those who want to have a hauntingly good PR. The best part of Spooky Sprint is you get to wear your costume! Whether you’re running as […]

Narrowleaf Lake Run

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

Brisk autumn running in Colorado – OH YEA! Join us for a family fun event with three distance options at the beautiful Boyd Lake State Park venue. What’s a “Narrowleaf” you ask? The Narrowleaf Cottonwood Trees are the most densely populated tree species at Boyd Lake State park. We thought the name was fitting and […]

MonsterDASH

Louisville Community Park 955 Bella Vista Dr, Louisville, CO, United States

Colorado's Longest running Halloween race....since 2006, we have changed the THEME to this race year after year! This 2025 Theme is:  Scary Clowns & Circus We wil have scary music and a CIRCUS Themes Expo at the start/finish. Hired Clowns on site and a circus atmosphere with Games, Hot Dogs, Pop Corn and Drinks. Stay […]

$35.00

PPRR Nielson Challenge

North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United States

Race Format The first time you run this event, you'll establish a base time for yourself. This base time is used to generate a handicap time. The handicap time is calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]

Colorado 24 Hour Run

Colorado Youth Outdoors 4927 County Rd 36, Fort Collins, CO, United States

Welcome to the Colorado 24 Hour Run! We aim to provide a fun, welcoming race experience that allows everyone to find a challenge, no matter where you’re at on your running journey. Want to see how far you can go in 6, 12 or 24 hours? Or achieve a new furthest distance? What about setting […]

$90 – $200

City Park 5K

City Park - Denver 1700 N York St, Denver, CO, United States

Get ready for the winter season while enjoying a race with your friends at the City Park 5k! 5k finishers earn a MEDAL! November is Worldwide Pancreatic Cancer Awareness month - let's kick off the month by running for a cause!  Consider adding a donation of which 100% goes directly to Pancreatic Cancer Research RIGHT […]

$27

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