This article is more than 6 years old

This article is more than 6 years old

A 30-metre (100ft) wide sinkhole has opened up in county Durham in the north-east of England, and it is so deep that its bottom cannot be seen.

The gaping void, thought to be the result of mine workings, was discovered on Thursday by Sam Hillyard, a Durham University academic, at Cowshill, in the rural area of Weardale – and it has since grown three times as big.

The 39-year-old had been out shooting rabbits and was returning to her home when she noticed the hole.

Hillyard's partner, John Hensby, a 71-year-old retired sales trainer, said: "Sam came back and she was looking quite shocked.

"She told me that a hole had appeared and I said I best go and have a look.

"At the time, it was about five metres round. Throughout Thursday night it got bigger and bigger until it was about three times that size on Friday morning.

"It is about 35 metres wide and you can't see the bottom of it.

"The sound was phenomenal. We could hear rumbling and smashing and crashing from down below – all of these great lumps of earth were falling in and falling in.

"If one of the dogs or the sheep fell in we would never see them again."

The couple fear the coming rain will make the hole bigger still.

The couple's home is between two former mines, Sedling pit and Burtree Pastures pit. Hillyard and Hensby live in the old pit master's home and the house is surrounded by sheep farms.

But one of the old mine shafts remains just metres from where the ground has given way.

Hensby informed Durham county council and Durham police of the hole as a precaution.

They are waiting to see if it gets any deeper, with downpours expected on Monday.

Hensby said: "With more rain coming on Monday we could see a lot more of the hole."