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Whether a race, special group ride, training opportunity, or cycling-related community event, the 303 calendar showcases it all.  To have an event posted here please follow this link:  Event Policy Submission & Guidelines.

IRONMAN 70.3 Boulder

Boulder Reservoir Boulder

Boulder   IRONMAN 70.3 Boulder kicks off at the pristine Boulder Reservoir with its spectacular Rocky Mountain backdrop. This even has been an athlete favorite for over a decade. IRONMANRead More

Horsetooth Tri Training Series

Horsetooth Reservoir 4200 Cr-38e., Ft Collins

Fort Collins   The Open Water Swim Series is an 10 week event consisting of a swim/run sequence. It is designed as a weekly practice & training opportunity for anyoneRead More

USAT Age Group Nationals

Lake Erie Cleveland

Cleveland, Ohio   USA Triathlon is heading back to Cleveland, Ohio, the "Rock 'n Roll Capital of the World!" The Olympic-Distance Age Group National Championship will take place on Saturday,Read More

XTERRA Indian Peaks

Eldora Nordic Center Nederland

Eldora   Welcome to the XTERRA Indian Peaks Triathlon.  On Saturday August 10th, 300 brave souls will depart in a time trial start on a chilly 1000 meter swim, followedRead More

Steamboat Triathlons

Lake Catamount Steamboat Springs

Steamboat Springs   Sprint Distance Triathlon, Olympic Distance Triathlon, Olympic Distance Aquabike, Olympic Distance Duathlon, & NEW Stand-Up Paddle-Board Options The Steamboat Triathlon features a sprint distance, olympic distance, aquabike,Read More

Chatfield Lake Classic OWS

Chatfield Reservoir Littleton

  Littleton   The Chatfield Classic will consist of a 1 mile swim followed by a 2 mile swim. In between the two races, there will be a short breakRead More

Chtafield Lake Classic

Chatfield Reservoir Littleton

Chatfield Reservoir, Littleton   The Chatfield Classic will consist of a 1 mile swim followed by a 2 mile swim.  In between the two races, there will be a shortRead More

Horsetooth Tri Training Series

Horsetooth Reservoir 4200 Cr-38e., Ft Collins

Fort Collins   The Open Water Swim Series is an 10 week event consisting of a swim/run sequence. It is designed as a weekly practice & training opportunity for anyoneRead More

The Cliff Backyard Ultra

Wellington Lake 21843 Stoney Pass Rd, Bailey

Wellington Lake, Bailey   The Cliff Backyard Ultra is a unique individually supported stage-style marathon swimming competition.  This swim offers a challenging swimming opportunity for long-distance swimmers.  In this event,Read More

Outdoor Divas Women’s Triathlon

Union Reservoir Longmont

Longmont   The 11th annual Outdoor Divas Sprint Triathlon on August 18th, awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for!Read More