Thrillseekers took on a teethchattering challenge for charity - jumping into 20 tonnes of icy water.
Undeterred by the already plummeting temperatures, about 100 daredevils signed up for the shiver-inducing Polar Plunge at Queen Elizabeth Olympic Park on Saturday afternoon.
Think the Ice Bucket Challenge but a whole lot frostier.
Many people - seemingly immune from the cold - sported fancy dress to jump into the freezing open-air pool, while other hardy souls stripped down to just their swimwear.
There was even a chance for children to get involved by jumping into the under 12’s paddling plunge pool.
Meanwhile, plungers wanting to lower their temperatures even further could sit atop a polar bear carved from ice.
Organised by Special Olympic GB, the toe curling event raised more than £25,000 for children and adults with learning difficulties.
Along with the glacial main attraction, the afternoon also featured music from London 2012 opening ceremony act Pandemonium Drummers who gave free workshops to children.
Sarah Ball, Special Olympic GB’s director of special events, said: “It was fantasic to see so many brave people take the plunge on Saturday.
“Despite the cold weather, everyone was in really high spirits and the atmosphere was great.
“As well as raising money, it was also a great opportunity to raise awareness of Special Olympics GB.”
Already a Stateside sensation, the Stratford Polar Plunge event was the event’s London debut.
To find out more about the Special Olympics, and upcoming fundraising events for the charity, visit specialolympicsgb.org.uk
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