Just done a quick trip to Naracoorte Caves National Park for several meetings - this is South Australia's only World Heritage Site, and one of 19 sites in Australia. We're all very familar with a number of the other sites, namely Uluru, Kakadu and the Great Barrier Reef - but Naracoorte is also pretty spectacular as well. The caves have acted as giant pitfall traps and have preserved the bones of megafauna that became extinct around 60,000 years ago - e.g. Marsupial lion, Thylacine or Tasmanian tiger, and the short-faced kangaroo. You actually get to see where the excavations were undertaken on the Victoria fossil cave tour (see photos below). There really is something for everyone here (recent burns with areas of vegetation regenerating, amazing flowers on some of the native plants, bats in their natural habitat which can be viewed via infrared cameras, Wollambi fossil centre which is actually a recreation of the megafauna (and associated plants) and interesting walks). I'll definitely be coming back to see more!
There is an article in the Faculty of Science, University of Adelaide escience magazine (issue 14, 2015) about the Naracoorte’s fossil caves and what they reveal about past biodiversity (see http://www.sciences.adelaide.edu.au/schools-resources/e-science/).