Extending approximately 650 km from east to west, the Nullarbor Plain runs from the south-western coast of South Australia to south-eastern Western Australia. It is bordered by the Great Australian Bight where it ends in steep cliffs. Its maximum altitude is about 200 m. Rainfall on the Nullarbor Plain is less than 250 mm a year and there is little surface water as most of it drains through porous limestone to form sink holes. Those, in turn, flow into underground caverns where subterranean lakes are formed. Discoveries of fossil bones and shells indicate that at one time the plain was part of the sea bed.
The Nullarbor is crossed by the Trans-Australian Railway (the train which traverses the route from Perth to Sydney is known as the Indian-Pacific after the oceans it conjoins) which contains the world's greatest length of straight track (479 km).
The first European to cross the Nullarbor Plain from east to west was Edward Eyre in 1841. The trek in the other direction was made by Alexander and John Forrest in 1870.
Despite a lot of belief that the plain's name is an aboriginal name, it actually comes from the Latin, meaning "no trees" (null arbor).