Dozens of swimmers plunged into near-freezing waters to enjoy a biting festive dip.
The hearty bunch leapt into a lake in west London, before swimming a 100m course, with some even opting to forego wetsuits.
Organisers of the Princes Club Polar Bear swim, which began last year when 16 courageous souls took to the water, had hoped around 50 people would brave the chilly weather for this year's event.
Rachael Wardle, 16, from Ruislip, west London, said the bracing dip was "something which had to be done".
"It was a bit crazy and very, very cold but I'm glad I've done it. I did it last year and I would definitely do it again. Maybe I'm mad but I loved it."
Bradley Hales, 19, the first of 51 to complete the course said warming up after the challenge took significantly longer than the swim itself.
"It was very cold - that's the main thing you can take from it," the university student from Staines, in Surrey, said.
"It was very fast, great fun and a good laugh - I think everyone had a good time."
Participants were later treated to a glass of warming mulled wine.
Organisers at the Princes Club waterski and wakeboard facility in Bedfont, west London, estimated the water temperature to be around two degrees Celsius.
