"Back with a Splash" will see travel companies, their employees, families and friends either swim, walk, boat or cycle the 42,700 miles of rivers, canals and inward waterways across the UK to mark World Health Day.
The event will start on the week commencing 7 April.
To get involved, travel organisations must inform the charity of how many miles it intends to travel in the week via its website, and ask colleagues to donate £5 to take part in the event via the charity’s JustGiving page.
