We’re delighted to have Macmillan as our RunThrough Triathlon Partner in 2026. Macmillan has spent more than 100 years helping people living with cancer. From the moment someone is diagnosed, we're there with all the information, support and guidance they need, to help everyone with cancer live life as fully as they can.

Take on a Super Sprint or Standard triathlon around Dorney Lake on Saturday 26th September 2026 and take the opportunity to race around this unique and inspiring Olympic venue!

The purpose built lake is perfect for the swim and the flat grounds lend themselves to a totally flat bike and run course, the ideal venue for a chip timed personal best. Each discipline will be accurately marked out with distance flags and we will have plenty of helpers to keep you on track and to encourage you all the way to the finish.

For those who don’t want to take part in the run, there is also an Aquabike (swim-bike) option, and for those who would like to compete as a team, there is a relay option, which allows 2 or 3 individuals to share the disciplines between them.