About Sidekick Tri

Sidekick Tri takes place at the iconic Dorney Lake, Windsor, on Friday 14 August ‘26, officially opening the Superhero Tri powered by Marvel weekend. It brings together the Super Partners, Corporate & Charity Friends who stand behind the Everyday Superheroes & it gives Sidekicks a Mission of their own. Sidekick Tri sets the stage for a weekend built on inclusion, impact & super-sized fundraising!

The Mission

Full Superhero Tri (Paralympic distance)
750m Swim
20km Cycle
5km Run

Take on the mission solo, or as a relay team of up to three, with each Sidekick taking on a stage.

An exclusive invitation

Sidekick Tri is exclusively for Superhero Series’ Super Partners, Corporate Friends & Charity Friends the organisations powering the UK’s most inclusive mass-participation sports events. Becoming a Super Partner unlocks access to Sidekick Tri, alongside year-round opportunities to champion inclusivity, & create meaningful, lasting impact. Not currently a Super Partner or Charity Friend but want to take part? We’d love to talk, get in touch here.