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Put on your running shoes for the 2023 Boston Triathlon

The 15th annual Columbia Threadneedle Investments Boston Triathlon returns this summer.

Athletes at the 2021 Boston Triathlon. Courtesy Boston Triathlon

The annual Columbia Threadneedle Investments Boston Triathlon returns to South Boston on the last weekend in August, hosting both Olympic and sprint distance triathlons along with Kids Splash & Dash races. 

Boston’s only triathlon once again heads to Southie—participants swim across Dorchester Bay, bike along the Southie shoreline between Carson Beach and Pleasure Bay, and run through Moakley Park. Find the full race course maps here. The event is USA Triathlon-sanctioned, meaning all USAT rules and regulations will apply. Folks of all experience levels are encouraged to participate, even if it’s your first triathlon. Event registration is currently open here.


The race is presented by ethos, which also organizes the Lobsterman Triathlon in Maine, and Boston Medical Center is the official race charity partner.

Last year’s Columbia Threadneedle Investments Triathlon, scheduled for Sunday, July 24, was postponed due to extreme heat, and took place on Aug. 21 instead.

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