It's not really the weather for an outdoor swim, but that didn't stop hundreds of brave bathers heading to Parliament Hill Lido in North London yesterday, for the 6th annual December Dip.
All swimmers who took part in the event, which is run by the Outdoor Swimming Society, were given a December Dip swimming hat, and were treated to mince pies, stollen and cheeky tipple to help them warm up afterwards.
Most participants swam the traditional two widths (56m), but some signed up to be Arctic Adventurers - and swam two lengths (120m) in very cold water that was expected to be somewhere between 0.1 and 6 degrees.
There was a special event for swimmers in fancy dress - last year one swimmer wore trunks made of tinsel - with a prize going to the best dressed.
Swimmers were warned that the water would feel painfully cold - but the organisers claim that the icy dip can result in a high that lasts for days. Brrrr.
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