Head of research at JM Finn, Sir John Royden, is looking to become only the 8th person to swim the entire length of Lake Geneva unsupported.

Sir John, 56, who successfully swam the English Channel in 1993, is hoping to swim the 42.8-mile Lake in 36 hours. He will swim non-stop, day and night, and tread water every hour whilst he is fed from a support boat.

The swim is in aid of The Brain Tumour Charity in memory of Sir John's sister, Emma, who succumbed to a brain tumour at th...