The COLDERBolder 5K takes place on December 5th on the CU campus; registration is now open! The sister race of the BOLDERBoulder, the COLDERBolder began in 2003 and has grown in popularity each year (so much so that it now regularly sells out). Offering a quick race, a festive atmosphere, and holiday goodies, it attracts runners, walkers, and dawdlers looking to experience a winter wonderland.
How to Take Part
The COLDERBolder consists of 13 invitational races, an open race, a walking wave, and a virtual race. Those who finished the 2025 COLDERBolder or the 2026 BOLDERBoulder can enter the invitational races, which are organized by pace to foster a more competitive atmosphere. Because everyone runs alongside those with similar race times, all participants have an equal shot at winning.
The open race is for those who don’t qualify for the invitational races or who want a more casual experience. This race allows people to run alongside friends and family, regardless of race time. The walking wave is not a race but rather a stroll; it’s for those who want to participate without breaking much of a sweat. The virtual race is designed to include those who can’t participate in person.
The Awards
COLDERBolder awards a finisher’s medal to everyone who takes part; it recognizes the top three finishers in each race (except the walking wave) with a special Cold Medal. As part of the registration fee, all participants receive an official COLDERBolder bib with an RFID timing tag and a holiday mini-feast upon finishing (complete with burritos, donuts, coffee, hot cocoa, and more).
Because the COLDERBolder sells out each year, race-day registration is not available. Enter soon!