By Jamie Obern
Close to the small village of Allendale, 15 minutes south of Mount Gambier in South Australia, there is an unremarkable cow paddock.
It looks exactly the same as the dozens of other cow paddocks we’ve passed but this is special.
We open the gate and our procession bumps across the field, stopping close by what appears to be an abandoned piece of wire mesh fence lying flat on the ground covering a hole. Amazingly this unremarkable surface environment hides a truly remarkable subterranean wonderland, which, over the last 40 years, has attracted many of the world’s greatest cave divers.
Beneath this particular cow paddock is one of Australia’s most spectacular cave diving sites, The Shaft. The cave was discovered in the late 1930s when a plough horse stumbled after putting its hoof through the 30cm entrance hole. Intrigued, the farmer lowered a weighted rope and discovered water seven metres below, with solid rock a further 40m down. It wasn’t until the mid 1960s before a diver was lowered through the entrance (which had been enlarged by rain) and discovered the 17m wide surface lake.
Using only very basic diving gear he descended to 21m and on his return reported a huge cavern which appeared to extend in several directions.
It was time to call in the cave divers. What the cave divers discovered was an enormous sinkhole, with fabulously clear water. The solid rock originally plumbed to 40m was the natural top of a debris pile, although it is now somewhat larger. The farmer disposed of the unwanted rocks in his fields by dropping them down the hole. From this rock pile the cave drops steeply away, reaching more than 120m at its deepest point, far beyond the range of the early explorers.
The first major mapping exercise of the cave was done in the early 80s … Read the full feature at
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