Colorado Triathlete

IRONMAN 70.3 Boulder
2025-06-14, 2026-06-13 | Boulder Reservoir, 5275 Reservoir Road, Boulder, CO, 80301, United States
Presale Registration for 2023 IRONMAN 70.3 Boulder opens at 10am MT on Thursday, August 4, 2022.

Tri Boulder
2025-07-19, 2026-07-18
As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in one eventful day! Join us for a full day of racing at the Rez.

Harvest Moon Long Course Triathlon
2026-05-31
The Harvest Moon Half Distance Triathlon: This event takes place at the beautiful Boulder Reservoir on May 31st, 2026 and we couldn’t be more excited to be back for another year. Est. in 2000 this Colorado classic provides the veterans to beginners a challenging, affordable, and competitive race with a local flavor. Whether this is your first event of the season, or a tune-up for a summer long course triathlon, don’t miss the Harvest Moon! The Aquabike portion is one of the fastest growing Aquabikes in the nation, while the duathlon is Colorado’s only long-course duathlon.

Tri Boulder
2026-08-09
Rocky Mountain Tri-Fest was established in 2023 to cater to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, to children looking to do their first triathlon.
The Sprint and Super Sprint gravel Tris are beginner friendly with the bike course on the gravel roads surrounding the reservoir. The road are graded and smooth, so you can use almost any bike, even a road bike with wide tires.
The Mini and SSS were created for the younger members of the family, but adults are more than welcome to tag along. These distance take place entirely inside the reservoir, and are 100% about having fun.
We are super excited to be able to offer the kids race for free in 2025. We hope that this will allow more families to join and an introduce this great sport to their children. Use code Rockymountainkids on the USAT membership link to take advantage of a free day license for you children as well.
What bike do you recommend? Do I have to use a “gravel” bike? The simple answer is you can race this course on a mountain bike, on a “gravel” bike, on a cyclocross bike, or even on a road bike with a minimum of 25mm tires and low psi. A tribike and disc wheel would be a little tricky.
For the kids races, anything goes Strider, tricycle, bmx, mountain bike, etc. Please make sure they have a helmet.
