Here’s one for your bucket list.
Located on the Great Australian Bight in Southern Australia, is the vast, featureless Nullarbor Plain – the world’s largest single piece of limestone, covering an area of 270,000 square km and extending some 1,000 km from the east to the west. The area is so flat that the Trans Australian Railway runs across its surface for about 483 kilometers in a completely straight line. On the surface of the plain there are areas of slight depressions where sparse rainfall has slowly dissolved away some of the limestone. There are also places where underground caves or sinkholes have collapsed to form dents in the surface. But mostly, the plain is horizontally flat and devoid of trees, as its Latin name suggests. The Nullarbor Plain ends abruptly at the spectacular Bunda Cliffs, comprising a 200-kilometer-long precipice curving around the Great Australian Bight.
Follow the link to see the pictures. Words just cannot do this justice.