Tantanoola Caves

Tantanoola Cave, named after the nearby town, is more or less a single big chamber, about 30m across and 8m high. It is smaller than other show caves in South Australia, but it is famous for numerous beautiful speleothems. It contains numerous of the rare helictites.
This cave is located inside Up and Down Rock, an ancient marine cliff towering over the highway. The Miocene bryozoan dolomite which underlies the Gambier limestone of the area was once uplifted along the Tartwaup fault-line. During the Pleistocene the sea shore was located right at this dolomite. The sea worked on the rocks and formed a cliff by continually destroying the rocks at the bottom of the cliff with the energy of the waves. This work results in sea caves, overhangs and a cliff face which is always more or less vertical. But then the sea receded, either because the sea level lowered or because the land was uplifted.