Colorado
Colorado Triathlon Calendar 2026-2027
Monthly updates for Colorado
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Explore the best triathlons in Colorado for 2026-2027! Our updated list features 18 exciting races across the region. Find your next race in Colorado below and join the running community at these great events!
May 2026
A long-running triathlon at Boulder Reservoir on May 31, 2026, featuring a half distance triathlon plus Olympic, sprint, aquabike, duathlon and relay options, with entry fees and a stated emphasis on participant safety.
An off road triathlon at Ridgway State Park featuring a trail run, SUP paddle and mountain bike leg with individual and team entries, including youth categories.
A USAT sanctioned triathlon in Loveland Colorado held once each summer on a Saturday morning in June. Race options include Sprint and Olympic triathlons, aqua bike, relay and SUP events with a lakeside, shaded venue and family friendly spectator area..
A multi sport triathlon at Boulder Reservoir featuring a sunrise swim, a fast bike course and a smooth run with the Flatirons as a backdrop. Multiple formats include Sprint, Olympic, aquabike, duathlon and relay options.
July 2026
Sheep Creek Triathlon in Antonito, Colorado on July 4, 2026 combines a one-mile walk or jog, three holes of frisbee golf and optional river inter-tubing depending on conditions. Entry and shirt purchase options are available.
A trail duathlon in Pagosa Springs on July 11, 2026, with three formats ranging from a kids run-bike to a 7 mile run with a 15 mile mountain bike. Fees include a race shirt, food, and awards, and proceeds support a local nonprofit.
Swim and run races for youth and adults in Colorado Springs as part of the Rocky Mountain State Games, pairing pool swims with runs on the Santa Fe Trail. USA Triathlon membership is required and age groups determine distances.
A multi-format triathlon at Boulder Reservoir on July 18, 2026, offering sprint, Olympic, long-course, aquabike and duathlon options plus relay categories; the event is produced by BBSC Endurance Sports with an emphasis on safety.
August 2026
Join this multi sport festival at Boulder Reservoir featuring gravel triathlons and aquabike races. With distances ranging from Super Sprint to relay options there are accessible events for individual athletes and the whole family.
A multi-category triathlon in Gunnison on August 22, 2026, featuring a 500 yard swim, 23K bike and 6.4K run. Events include kids, adult, and team relays with awards, participant shirts, and a post race gathering.
Multisport races at Boulder Reservoir featuring swim, bike and run courses with the Flatirons as a backdrop. Offers Sprint and Olympic triathlon formats plus duathlon, aquabike and relay options.
September 2026
Experience a scenic triathlon at Lake Nighthorse in Durango. Choose between Sprint and Olympic distances featuring a lake swim, road cycling with climbs, and a gravel run with spectacular views.
Durango's Valkyrie Relay is a scenic multisport team or solo challenge across trails, roads, lakes and the Animas River with full and sprint courses. Teams up to nine or solo Ultra Heptathletes combine running, biking, SUP and paddling.
A sprint triathlon in Montrose on September 26, 2026 with youth, adult, team, and family divisions. USAT membership is required and proceeds support the Montrose Recreation Foundation.
A two-day trail and bike event in Estes Park featuring 31-mile bike and run options, a 15-mile heavy half, and a 62-mile duathlon, with rugged trails, significant climbs, and aid stations supporting competitors.
October 2026
A sprint triathlon in Alamosa, Colorado on October 3, 2026 featuring a 400-yard swim, 10-mile bike and 5k run. Individual and 2- or 3-person team entries, age-group awards and finishers' medals.
A high elevation swimrun in Fort Collins combining open-water swims at Horsetooth Reservoir with single-track trail runs in Lory State Park. Three distances from 6 to 23.5 miles, mandatory gear requirements, and a 15:00 finish cut-off.