Huge Coastal Sinkhole That Could Suck People Into Ocean Appears Overnight

Visitors to a clifftop path, where a huge sinkhole has appeared overnight, have been urged to stay away in case they are "sucked out into the ocean."

The sinkhole appeared on a coastal trail in the fishing town of Robe on south Australia's Limestone Coast, the District Council of Robe said in a Facebook post.

The hole sits close to a geological phenomenon known as a blowhole, or marine geyser, which is near the red and white Robe Obelisk, which was erected in 1852 to guide ships.

The sinkhole at the popular tourist destination emerged before the start of a long weekend in most parts of Australia, held to celebrate Queen Elizabeth II's birthday on June 14, when some people will be heading to beauty spots.

Calling it a "Woe Hole," the council said it had formed overnight after a collapse.

"Waves are actively scouring the area beneath the hole and it is still collapsing," it said, adding that an inspection on showed it is expected to increase in size.

The council urged members of the public to stay away from the hole as its surface was very thin.

People taking a morning walk in the area first spotted the hole, the TripleM radio station reported.

James Holyman, chief executive officer of Robe District Council, told the outlet the hole was the size of half a tennis court. Most tennis courts are 78 feet long.

Holyman told Australia's ABC outlet that people who want to look at the hole should keep outside of areas where flags have been placed.

"It's a fair way down and the Southern Ocean is fairly churned with big rollers [waves] coming in there.

"If you went in there, you'd be sucked out into the ocean."

Holyman said: "There's no warning when these things give way... You don't get a warning. If that area drops it just happens."

Explaining what caused the sinkhole, he told Triple M: "The blowhole hasn't blown for a number of years, but the energy of the waves have eroded further in under and that's where we've had this collapse.

"Having the ocean and limestone cliffs, we will have erosion and undercuts over time and they collapse every so often.

"This is an area that has been quite undercut and for it to fall a little bit inland, rather than directly on the coastline is a little unusual."

According to Triple M, the council will work with Flinders University and coastal engineers to study the sinkhole and to understand how to protect the coastline.

Patrick Hesp, a coastal studies expert at Flinders University, told ABC the limestone area likely collapsed due to recent heavy rain and ocean swells.

robe obelisk
A stock images shows the Robe Obelisk on Cape Dombey, built in 1852. A sinkhole has opened up near the Obelisk. Getty Images