The NULLARBOR PLAIN is part of the area of flat, almost treeless, arid or semi-arid country of southern Australia, located on the Great Australian Bight coast with the Great Victoria Desert to its north. It is the world's largest single exposure of limestone bedrock, and occupies an area of about 200,000 square kilometres (77,000 square miles). At its widest point, it stretches about 1,100 kilometres (648 miles) from west to east across the border between Western Australia and South Australia. (It really illustrates what a large country/island Australia is).
Historically, the Nullarbor, considered by Europeans to be almost uninhabitable, was used by the semi-nomadic Aborigines, the Spinifex and Wangai peoples. The first Europeans known to have sighted and mapped it were an expedition led b Pieter Nuyts in 1626-27. While the interior remained little known to Europeans over the next two centuries,the name Nutytsland was often applied to the area adjoining the Great Australian Bight. It survives as two geographical names in Western Australia: Nuytsland Nature Reserve and Nuyts Land District. (Note: Our beautiful Christmas tree is named Nuytsia floribunda which would also be named for Pieter Nuyts I would imagine).
Despite the hardships created by the nature of the Nullarbor, European settlers were determined to cross the plain. Although Edward John Eyre described the Plain as "a hideous anomaly, a blot on the face of Nature, the sort of place one gets into in bad dreams" be became the first European to successfully make the crossing in 1841. Eyre departed Fowler's Bay on 17 November, 1840 with John Baxter and a party of three Aboriginal men. When three of his horses died of dehydration, he returned to Fowler's Bay. He departed with a second expedition on 25 February, 1841. By 29 April, the party had reached Caiguna. Lack of supplies and water led to a mutiny. Two of the Aborigines killed Baxter and took the party's supplies. Eyre and the third Aborigine, Wylie, continued on their journey, surviving through bushcraft and some fortuitous circumstances such as receiving some supplies from a French whaling vessel anchored at Rossiter Bay. They completed their crossing in June, 1841.
A proposed new state of Auralis (meaning "land of gold") would have comprised the Goldfields, the western portion of the Nullarbor Plain and the port town of Esperance, Its capital would have been Kalgoorlie. (I have never heard of this plan nor whose idea it was...More reading apparently needed).
"Crossing the Nullarbor", for many Australians is a quintessential experience of the "Australian Outback". Stickers bought from roadhouses on the highway show "I have crossed the Nullarbor, and can be seen on vehicles of varying quality or capacity for long long distance travel. The process of "beating the crowds" on overbooked air services at the time of special sporting events can also see significant numbers of vehicles on the road.
Crossings in the 1950s and earlier were significant as most of the route then was a dirt track. Round-Australia car trials (the Redex Trials) used the Nullarbor crossing for good photo shoots of cars negotiating poor track. (I knew two young women who crossed the Nullarbor (there and back) in an Austin A40 and I remember Margaret writing in a postcard from the other side that "June knew every pothole on the road and never missed one." Quite a trip for the two of them on an unsealed road back in 1949).
The Indian Pacific crosses the Nullarbor Plain from Perth to Sydney via Adelaide, twice weekly in both directions. The full journey covers a distance of 4,352 kilometres and lasts three nights. This is the most direct route across the Nullarbor Plain, running between Kalgoorlie and Port Augusta. As stated in the "Outback Australia travel guide: "When the scenery starts living up to its press you can always bury your nose in a book".
There is a lot more information about how the Nullarbor was formed (it was formerly a seabed) with explanations about the variations in the limestone etc. You will find it all on Wikipedia from where I got this information and most of the pics.