|Famous eroded cliffs stacks in ocean waves (Pacific Ocean). 12 Apostles at Great Ocean Road, Victoria, Australia The Twelve Apostles is a collection of limestone stacks off the shore of the Port Campbell National Park, by the Great Ocean Road in Victoria, Australia. Their proximity to one another has made the site a popular tourist attraction. The apostles were formed by erosion: the harsh weather conditions from the Southern Ocean gradually eroded the soft limestone to form caves in the cliffs, which then became arches, which in turn collapsed; leaving rock stacks up to 45 metres high. The site was known as the Sow and Piglets until 1922 (Muttonbird Island, near Loch Ard Gorge, was the Sow, and the smaller rock stacks the Piglets); after which it was renamed to The Apostles for tourism purposes. The formation eventually became known as the Twelve Apostles, despite only ever having nine stacks. In 2002, the Port Campbell Professional Fishermen's Association unsuccessfully attempted to block the creation of a proposed marine national park at the Twelve Apostles location, but were satisfied with the later Victorian Government decision to not allow seismic exploration at the same site by Benaris Energy; believing it would harm marine life. The stacks are susceptible to further erosion from the waves.