The first ever Utterly Buttermere open water swim is taking place. 200 people are taking to the water to swim 1.5k, 5k or 10k around the circumference of Buttermere.
The challenge is organised by Head to the Hills and High Terrain Events in association with the National Trust.
Organisers hope it will become a regular feature on the open water swimming calendar.
More top news
Do you know what's been happening in Cumbria and the south of Scotland over the past seven days? Test yourself in our weekly news quiz.
Two small creatures from thousands of miles away could create big problems for Cumbria's rivers.
A look ahead at the forecast for the Border region.