What is Open Water Swimathon?

At Open Water Swimathon, you will have the opportunity to participate in an individual challenge (400m, 1.5K, 2.5K or 5K) or a team challenge (1.5K or 5K), perfect for both experienced open water swimmers, and those transferring from the pool to the open water for the first time.

Join Cancer Research UK and Marie Curie raise as much money as possible for two causes close to the nation’s hearts. This is your chance to fundraise for two incredible causes.

And remember… you're not getting in the open water alone! From the moment you sign-up, you will receive updates and helpful tips from the Open Water Swimathon team, helping you and guiding you in the lead-up to the event!

Register your interest and be the first to hear about early bird prices!


Not close enough to any of the host venues? Offered sessions not suiting your schedule? There are lots of reasons why you might not be able to attend an Open Water Swimathon organised session, but that does not mean that you cannot take part.

The MySwimathon challenge has been designed for those that can’t attend an organised session but don't want to miss out.

To offer you more flexibility with your open water swimming challenge, take on MySwimathon and choose your own venue and swimming time.

Please note, MySwimathon is NOT part of an organised Open Water Swimathon session. 

You will still be able to raise money for a fantastic cause, and of course to challenge the whole family, your friends and your colleagues to take part as well.