Half Marathon

Fast, flat and shady, the Colfax Half Marathon is the only race to run through Denver Zoo! Denver’s springtime half marathon takes runners on a one mile trek through the zoo, through historic neighborhoods, on eclectic Colfax, and through the Aurora Arts District & Aurora Fire Station #1.  The LIVE Colorado Firefighter Calendar will cheer you on at Mile 11 – a runner favorite.   Great mountain views along the way – and then a terrific after party in City park!

Virtual Photo Tour

Cruise to the bottom of the page to take a virtual photo tour of the sites on the course!

Runner Perks

Tech race shirts and awesome finisher medals with detachable mini-medallions for your keychain or necklace. Free runner tracking and digital on-course photo! Virtual race bag with great offers. Don’t miss the awesome afterparty and Michelob Ultra Beer Garden lakeside in City Park.


Set a new event record, win $1,000. Set a new state record, win an additional $1,000. See the times to beat here. Age group awards are great keepsakes! Overall and masters awards are based on gun time (1st, 2nd, 3rd). Age group awards are by chip time (1st, 2nd, 3rd) in categories: 19 & under, 20-29, 30-39, 40-49, 50-59, 60-69, 70+. Athletes with disabilities click here for details regarding awards categories.

Run for Charity

Run for one of the largest Charity Partner programs in the country! Over 200 charities participated in 2019. Choose a charity to run for when you register and they will contact you

Training & Runs

Announcing the Colfax Training Series! Our Colfax Marathon Ambassadors will join Featured Running Clubs and running stores with Colfax drawings for great schwag. Check the TRAINING section for the up-to-date calendar – and great training tips.

Packet Pick Up & Race Day Logisitics

Pick up Race Packets Friday and Saturday, May 15-16, 2020 at the Health & Fitness Expo. No Race Day Packet Pick Up. Detailed race day logistics will be posted in April.

Photo Tour

Hover over each photo to learn fun facts!