Yorkshire Dales national park, England
A potholer is winched into Gaping Gill, the largest cavern in Britain.
The cavern is only open to the public two times a year, allowing people to be winched from a hole in the roof and up again for a fee of £15.
The drop from the moor top to the bottom of Gaping Gill Main Chamber is 110 metres, the same height as St Paul’s Cathedral.
Image Credit: Photograph by Danny Lawson/PA