No doubt, Australia has its fair share of long, lonesome routes. But the mother of all those routes is the crossing of the Nullarbor plain. 1200km of emptyness between Norseman and Ceduna.
The Nullarbor has just about everything that makes it the last place you want to travel with a bicycle: endless monotone landscape through semi desert and bush. Yet still (or because of) it attracts cyclists. Nowhere I meet more other cyclists. In terms of supplies and water the route is not too difficult as there is a roadhouse every 200km.
The attractions of the road are the 'Ninety Mile Straight', a 147km dead straight road without any curves, the Bunda Cliffs from where there are great views over the ocean and plenty of endless straights through barren landscapes.