Harvest Moon Triathlon

The Harvest Moon Half Distance Triathlon: The 26th edition of this event takes place at the beautiful Boulder Reservoir on September 13th, 2025 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 final event of the season, or a tune-up for a fall 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.