Triathlon Calendar near Shelter Island 2026-2027

October 2026

Cross Duathlon Individual 1.6 11.5 1.6 mi Duo 2 12 2 mi

23rd Annual Serpent's Back Mountain Bike Duathlon in Montauk, NY on October 11, 2026, featuring individual run-bike-run, bike-only, and two person relay options.

Oct

17

Sa

Brewathlon

Montauk | 20 mi from Shelter Island

Multisport Brewathlon 1 3 mi 3 10 km

A four-person team relay at Montauk Brewing Company on October 17, 2026 featuring running, rowing, and cycling legs, with proceeds supporting OMAC.

July 2027

Jul

11

Su

Jamesport Triathlon

Northville | 15 mi from Shelter Island

Triathlon INDIVIDUAL CHARITY SLOTS 500 m 25 km AquaBike 500 m 25 km Individual Adult Triathlo... 500 m 25 5 km Individual High School Tr... 500 m 25 5 km

A July 11, 2027 triathlon at South Jamesport Beach with a 500 m swim in Peconic Bay, a 25 km bike and a 5 km run plus multiple race formats.

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