These caves are part of the world's largest contiguous limestone karst system. This karst landscape, created by water dissolving the limestone, spans some 200,000 square kilometers.

The caves are as important for their geological value and what they can teach us about Australia's past, as they are for the unique animals they house, the fossils they hold and their beautiful and unusual cave decorations.

The Nullarbor Plain is the land of the Mirning people. Their Dreaming, associated with the Great Australian Bight, recalls oral histories of changing sea levels.

The Mirning have actively traversed the plain for millennia. Their artwork in its caves, extensive flint mining and artifacts scattered over its surface provide evidence of their presence.

But it's only in modern times that the plain's natural values have been threatened. The threats include invasive species, such as foxes, cats, camels and buffel grass, climate change and, perhaps most detrimentally, human activities. Mining, wildlife poaching, uncontrolled tourism and large-scale development, for example a proposed green energy project, could impact much of what makes the Nullarbor Plain so precious.