Dozens of swimmers took part in the bi-annual Cold Water Swimming Championship at Tooting Bec Lido on Saturday while wearing novelty swimming hats.
Around 650 competitors from around Europe braved the cold water and showed off their silly hats.
Swimmers were pictured wearing a dalek, a seagull and even a dragon with red smoke coming out of its mouth.
Other ambitious designs included a tray of hot drinks, a turtle sculpture and a quirky headdress made of balloons.
According to ITV News, the water was 3C and competitors took part in the 30-yard traditional 'head-up' breaststroke, the freestyle dash and a group jump-in.
There was a sauna, hot tubs and mulled wine to warm them up after the swim.
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