The Twelve Apostles
(Taken from an article in The Sunday Times)
The 12 Apostles is the name given to a collection of natural limestone stacks that rise up to 46m from the sea off the coast of Port Campbell National Park, Australia. The Twelve Apostles are located along the spectacular Great Ocean Road, a scenic route that starts approximately 97km southwest of Melbourne and winds 240km along the picturesque coastline.
Twelve Apostles Australia
They were originally named the ‘Sow and Piglets’. Located near Loch Ard Gorge, the Sow was Muttonbird Island, with the piglets being the smaller surrounding rocks.
The Twelve Apostles were formed by erosion of the original coastline, which began 10 to 20 million years ago, and constant action of the sea on the limestone slowly wore down the rocky cliff, gradually leaving individual rocks.
The cliff is still being eroded at a rate of about 2cm each year, and in the future is likely to form more ‘Apostles’ from the other rocky headlands that line the Victorian coastline. The stacks are varying heights and thicknesses.
The erosion is ongoing: over the years the number of limestone rocks visible in the formation has decreased.
There are not actually twelve stacks now, a number have fallen over entirely as their bases are being continually eroded by the force of the waves, diminishing to seven stacks for now.
From the lookout, you can only see a number of the Twelve Apostles. The others are located behind the rocky headlands that line the Victoria coastline, or hidden by other rocky outcrops. But their close proximity to one another has made the site a popular tourist attraction. Hundreds of thousands of tourists drive the route each year to see the natural landmarks.
In June 2009, a 33ft-long archway in the 12 Apostles area crumbled away. In 2005 one of the 230ft limestone towers crumbled into the sea in front of a family of tourists, who captured the moment on camera.
Another victim of the erosion was London Arch, located near the 12 Apostles, which had formed a double-span natural bridge to the mainland. One of the arches collapsed in 1990, leaving two tourists stranded on the outer part of the enormous rock. They were rescued by helicopter.
Experts calculate that waves chip away a few millimeters from the limestone formations and adjacent cliffs every year.
John Sherwood, an environmental scientist with Deakin University, said that Victoria’s unusually wet winter would have contributed to the major collapses.
“The extra weight as the formations have become more saturated with water, and the lubrication of cracks and joins by the water, can contribute to these things occurring,” Dr. Sherwood told The Times. ”So these two circumstances can come together and tip the balance of the formations.”
He said that the area was eroding rapidly because of the softness of the limestone rocks and the battering it received from the Southern Ocean.
As for the name 12 Apostles, Parks Australia said that it would not change it despite the dwindling number of limestone pillars.
“It will always be the 12 Apostles,” Ms. Curkpatrick said. “It remains unique no matter how many apostles come and go.”