THIS is the horrific moment a terrifying sinkhole opened up in a retired couple’s backyard before they made a chilling 120-year-old discovery.
Shocked neighbours told Lynn and Ray McKay there was a giant hole next to their Queensland home on Monday morning.
Alarmed McKays rushed their backyard to find the eerie hole - at which point it was about a metre wide.
Mr McKay told ABC News: "I came out and I see a hole in the ground."
"It was only a little one, around one metre, but it kept getting bigger.
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"We were seriously shocked after seeing it."
What followed next was a nightmare for the retired couple who did not have the slightest clue about the terrifying event.
By the next day, the hole had swollen up to become a huge cavity which was measured to be around 15 metres in diameter.
Queensland Utilities were called, in the belief that a water pipe had burst.
The McKays, however, were told there were no related pipes in the area.
But they soon learned about the chilling past of their property.
The Mayor of the area Paul Pisasale broke it to the couple that their house was built above a mine shaft from the coal mining past that dates back to 1885.
"We identified the fact that there's a shaft put in here many many years ago.
"The yard hole was the collapse of an exploratory shaft dug between 1903 and 1920 that was never documented properly by the miners.
“It was just a shaft that they created. One thing about back then, they were very bad at keeping records."
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By Tuesday evening, McKays' house was abuzz with staff from the mine who took on mammoth the job of repairing the giant sinkhole.
The property was then cordoned off and the retired couple was moved out temporarily.
A review of historical mine maps and plans in the area is now underway as part of a probe into the hole, according to a Department of Natural Resources and Mines spokeswoman.
"The department is working with the Department of Environment and Heritage Protection to determine an appropriate method to pump and dispose of water from the sinkhole," she added.
This was the second time the McKays witnessed huge damage to their property.
They previously lost all their possessions in the 2011 Queensland floods which damaged their home.