I went swimming at Wylie's Baths today. The seawater temperature was 16.5 degrees celsius, and the air temperature was around 12 degrees. Hearty stuff, I thought, until I remembered going for a winter walk around Hyde Park's Serpentine when I was in London in January. The weather was bitterly cold - sections of the lake were frozen. As we walked past the Serpentine Lido, I thought about how cold winter swimming in the UK would be.
Yes, apparently, they really do break the ice to go for a swim.