Cave divers find 100m-long underground tunnel on Limestone Coast
By Josh Brine
ABC South East SA
Topic:Geology
6m ago6 minutes agoMon 10 Mar 2025 at 8:19pm
A drone photo of a man standing on a ladder descending into a submerged cave.
Cave explorer Josh Richards standing in the entrance to Pines Cave. (ABC South East SA: Bec Whetham)
In short:
A group of divers has found 100 metres of underground tunnel extending from Pines Cave, near Tantanoola.
The tunnel comes within 15m of another cave, with hopes a path between the two can be found.
What's next?
The Soggy Wombats group says it will continue exploring the tunnel and other caves in the area.
Cave explorers have pushed through narrow gaps in rocky walls to uncover an extra 100 metres of tunnel on South Australia's Limestone Coast, with hopes it may link separate caves together.
The Soggy Wombats group found and named the Crazy Wombat tunnel, which extends north-west from Pines Cave at Tantanoola.
The newly-discovered tunnel comes within 15 metres of the nearby Stinging Nettle Cave, with Soggy Wombats' team leader Josh Richards hopeful the path between the caves can be completed.
"We've found no obvious ways on at this point but we're still poking around," he said.
"The idea that someone could jump into one cave and pop up in the other, that's very exciting."
Searching for a connection
The tunnel starts from a section of the cave known as the Crazy Czech Room, which is only accessible to advanced cave divers.
From there, the divers squeezed through a rock pile and dropped down into a large room they called the "Void".
"It's black and the water keeps the silt suspended for a very long time," Mr Richards said.
"As soon as a diver goes through, it becomes quite cloudy and difficult to navigate."
A cave diver wearing a yellow helmet, blue mask and black wetsuit squeezes between rocks.
Josh Richards squeezing through a narrow restriction in Pines Cave. (Supplied: Josh Richards)
After the Void, the Crazy Wombat tunnel briefly heads south-west before turning north-west again.
"It's crystal clean. It's very white limestone," Mr Richards said.
An overhead shot of a sinkhole surrounded by pine trees and a road on the right.
The Pines is one of several dive sites in the area. (ABC South East SA: Bec Whetham)
The team is hopeful that eventually a tunnel can be found all the way to the large Tank Cave about 2 kilometres to the north-west.
"[100 metres] might not sound a lot when you have 2km to go, but it's 100m in the right direction," Mr Richards said.
"We know there's water flowing from Tank Cave into where we are now in Pines, and so we just need to find a way between the two."
Previously, Mr Richards and fellow diver Matthew Aisbett found an extension of the Engelbrecht Cave under the city of Mount Gambier.
Two cave divers in black and red wet suits prepare their diving tanks, with pine trees in the background
Soggy Wombats Corey Auld and Josh Richards get ready to dive Pines Cave. (ABC South East SA: Josh Brine)
While Mr Richards said the group took every precaution possible, the exploration required "calculated risks".
"I don't like to say that it's risky because we plan everything out and reduce the risks as much as we can," he said.
"But there's an element there where you're a long way from home and, if something goes wrong, you have to make sure you have back ups in place to get back to the surface safely."
Exciting possibilities
Cave geologist Ian Lewis was also a cave explorer from the late 1960s.
A man with white hair and a bear closely examines a rock wall.
Ian Lewis says there are dozens of opportunities to look for cave extensions. (ABC South East SA: Bec Whetham)
He said the science had pointed to the theoretical possibility of linking up caves.
"Now people like Josh who are burrowing around and checking behind each rock in the cave or finding an extra room … they're starting to make that a reality," he said.
"There's a whole zone there where we know of a handful of caves.
"There's, I think, quite a fascinating possibility that caves might be able to start being linked up."
An underwater shot in a water-filled cave, with rocks formations
The Soggy Wombats hopes to connect to Tank Cave, 2 kilometres to the north-west. (Supplied: Richard Harris)
Mr Lewis said he thought there were probably "a dozen or two" opportunities to look for more extensions in already discovered cave systems.
"I know how exciting it is and how much hard work divers do to discover and find somewhere no human being's ever been before,"
he said.
"For them it's just a great buzz and a challenge."
A man in a black we suit with an orange helmet walking down stairs.
Josh Richards makes his way down into Pines Cave. (ABC South East SA: Josh Brine)
Mr Richards said the team was already working on other projects, including going further along the Pines Cave tunnel.
"We're always on the hunt for the next cave to go and look at and map, create a 3D model for and then be able to share with everyone," he said.
ABC South East SA — local news in your inbox
Get our local newsletter, delivered free each Friday
Your information is being handled in accordance with the ABC Privacy Collection Statement.
Posted6m ago6 minutes agoMon 10 Mar 2025 at 8:19pm
Copy link
X (formerly Twitter)