The Great North Swim at Windermere has gone ahead after being delayed by strong winds and heavy rain.
About 5,000 people took part in the two-mile swim across the Cumbria lake. In past years, the three-day event has attracted up to 10,000.
Philippa Morrow, of organisers Nova International, said the delay had been "really disappointing".
She added they had postponed the event because of "the safety of the swimmers being our number on priority".
A one-mile event on Saturday was cancelled and Friday's events were included in Sunday's schedule.
Nova International said they postponed the event because the wind would have affected the operation of the safety kayakers and also made swimming conditions extremely challenging.
A full refund will be offered to those unable to take part.