Calling all cold-blooded runners, rebels, and fitness junkies!

The ColderBOLDER 5K on December 1, 2018, is open to everyone. So layer up, grab a hat, and join us. Oh yes you can!

Race, Run, Jog, or Walk

We want you to have the time of your life no matter how fast you are, even while freezing your buns off!

The Course

Wind through the scenic University of Colorado campus, the course finishes inside the toasty Balch Field House.

CB Expo

After you finish, check out the expo for great food and drink samples, and tons of other schwag.

Finish Line Party

The perfect way to end your 5K is running into the Balch Field House to celebrate with friends and family. Watch the Cold Medal Ceremony while you enjoy your free goodies.

The ColderBolder

This 5K is a little different, but so are those of us who enjoy running in the cold. It is actually 13 individual races. The top three men and women in each race win Cold Medals. That’s 78 medalists total. 

The First 12 Races

These are for people who participated in the last BolderBOULDER. Each individual race puts people together who are about the same speed. Why? So everyone has a shot at winning. For example, if you finished the BolderBOULDER in 52 minutes you would race against people who finished between 52-54 minutes. It’s your chance at personal glory and eternal fame. You got this. 

The 13th and Final Race 

This is open to everyone, runners, joggers and walkers. We all want to stay fit over the holidays, and we want everyone to be able to participate. So, break out in a cold sweat with us. Let’s pour cold water on those winter blues. 

We’ve Got Your Back

We know how you like to be treated.

No hidden fees!

That’s right.

We’re different. We know how you like to be treated. That’s why we are committed to complete TranspaRUNcy around our events.

Can’t make it?

No problem!

No other race offers this. Learn more.

Registration Pricing

New beanies coming in 2018!

ColderBOLDER 2017 Video

Start Winter on the Right Foot.

ColderBOLDER 2018 Countdown. Dec. 1, 2018.









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We Couldn’t Do It Without Our Partners

Oskar Blues

Official Brewery and Anti-official Recovery Drink of the ColderBOLDER.


Our Official Bank has been keeping Coloradan’s financially fit since 1963.

Clif Bar

Fuel up with our Official Performance Nutrition Sponsor.

Boulder Running Company

Gear up for the cold with our Official Running Company Sponsor.