Swimming without being swallowed
If you enjoy swimming, you might have tried splashing about with some flippers - or maybe floating on a rubber ring.
But how about swimming with whales?
Philip Hoare wouldn't recommend swimming with the largest mammals on earth as being the safest thing to do. But he has been obsessed with whales ever since he grew up by the sea in the south of England.
It was on a trip to Cape Cod in 2001 that Philip first saw a whale in the wild.
It was a sperm whale. They're 65 feet long and have 42 huge ivory teeth.
Philip was very scared.
Sperm whales have been known to swallow humans whole. People are then killed by the whale's gastric juices.
Philip told Outlook's Matthew Bannister that despite the risks, he still feels a deep connection to the creatures.