Torrential rain over the Christmas break has caused a 130ft-deep and 160ft-wide hole to form in the Peak District.
The growing hole that was part of the Nether Slaters Mine in Foolow, caved in overnight after water eroded the earth underneath, causing the whole area to collapse.
Caver Mark Noble, 58, from Eyam, said he saw the hole during a walk on Christmas Day, but believes the land began to fall a couple of days before.
He said: “I heard about it in the pub on Christmas Eve so had a walk up there the next day. It pretty much appeared over night, in a couple of hours.”
Mark said he has explored the caves at Foolow in the past as huge cavities were left in the area from an old lead mine.
He added: “It’s a massive hole and it’s getting bigger all the time.
“It’s probably increased by about ten per cent since it opened up.”