It was the biggest Christmas Cup (Coupe de Noël) this year than ever before. 4,000 people leapt into Lake Geneva over the weekend.
The event has been going on since 1934 – although there have been a few cancellations over the years.
Despite the air temperature at 4 degrees and the water at 8.6 – many kept up their sense of humour and swam with costumes and even fondue sets.
For those brave enough, there was a reward at the end – a warming spa bath.
WRS caught up with Lianne Gonsalves and Callum Brindley, President of the swimming group Nageu-ses-rs du Rhône, who were thawing out after taking part in the swim.