The shortest route from Adelaide to Perth is 2680 kilometres. This is if you make the trip in a relatively straight and boring fashion without allowing for stopovers or diversions. It also takes you via Kalgoorlie and through the desert to Perth, whereas an alternative and longer route takes you along the south west coast of Australia, through Esperance, Albany and other coastal hotspots. This second route will be closer to the 3000 kilometre mark. Id recommend taking the diversions- this is the kind of journey most people only make once, so you may as well include some interesting sights Otherwise your memories will just be long straight roads, dry shrubbery, lots of blue sky, dead kangaroos... you get the picture! That said, if you do it properly, this is one of the most epic journeys you could possibly take in Australia.
Starting out in Adelaide, the first leg is a 320 kilometre drive to Port Augusta. You could go straight down Highway One, or take a more leisurely drive through the lush wineries of the Barossa Valley. Either way, overnight in Port Augusta before attempting the next leg in the journey, which takes you to Ceduna and the start of the Nullarbor Plain. This second leg takes you across the Eyre Peninsula, and again you have two options as to which route to take. An extra 280 kilometres takes you via Port Lincoln, the hub of the Eyre Peninsula and a pretty coastal town surrounded by sheltered beaches and impressive lookouts. If you bypass Port Lincoln its a straight run into Ceduna, the last place where there is any mobile phone coverage for some time, and a great place to stock up on supplies.
The next 1220 kilometres are going to be spent crossing the Nullarbor Plain, the end of which lies at the town of Norseman, well across the WA border. When making this crossing there are a few things you need to remember. Firstly and most importantly, water is in very short supply. Ensure you have taken more than enough for your own drinking purposes and for the radiator in your car. Secondly, a container with extra fuel in it is also a good idea. Most fuel stops along the way are only open during the daylight hours for some reason, and you dont want to be caught short. Also, you need to keep an eye out for kangaroos. For various reasons they are attracted to the side of the road, and stand like sentinels watching vehicles pass. They are easily frighted into running into your path, as the hordes of dead ones on the road testify to! So be careful.
Although the highway through the Nullarbor (the Eyre Highway) runs parallel and close to the shore for much of the way, there are few opportunities where you get to see the ocean, so detours are needed to appreciate the coastline here. When taking detours you are likely to bump into surfers camped out amongst the dunes, hunting the perfect wave. Cactus Beach is a popular surfing spot, and is found by turning off from the highway at Penong. When driving through Penong look out for the old windmills scattered through the fields alongside the highway- a novelty for photographers.
300 km from Ceduna is the Nullarbor Roadhouse, where there is a motel, restaurant and caravan park, as well as the opportunity to refuel. From here it is 186 kilometres to the state border, which takes you past the amazing Bunda Cliffs, which stand 80 metres high and are definitely one of the highlights of the trip. At the borderpost there is a fruit quarantine station, where you will be searched for any fruit. From here there is little more than flat earth and the occasional settlement until you reach Norseman. Eucla first, and then Mundrabilla, over the Madura Pass (some interesting feature here in an otherwise monotonous landscape), and on to Cocklebiddy. From Cocklebiddy its just over 430 kilometres to Norseman. Now well into WA, its time to congratulate yourself- you've crossed the Nullarbor!
After Norseman head south to Esperance, and then drive up the beautiful coast of South West Australia. Lush and brimming with feature and stunning scenery, it will provide a welcome contrast to the bare and open land you have travelled through. Its about 1000 kilometres from Esperance to Perth via Albany and Bunbury, and its a fitting final leg to an epic journey in which you would have seen a whole lot of Australia!