Travelling in Australia?

We want to travel from Cairns to Sydney/Melbourne Next August/Sept for three weeks. What is the cheapest way to do this taking acc. into account? Bus, train, car hire etc.

I'd have thought flying there would be the easiest way, as well as being cheaper (via Jet* or Virgin Blue) than any of the other options.

Cairns to Sydney, let alone Melbourne, is a bloody long way!

Just hire a car when you get there.

Jetstar and Virgin Blue have great cheap deals. If you want a bit more then Qantas flies to your destinations as well. although qantas is more expensive.

Flying would definitely be your best option, unless you wanted to see the sights of the travel, then you might have to get buses, hiring cars here is expensive. But that would make for a long journey, and a lot in fuel, and fuel is not cheap here either, being around $1.20 p/L in Qld... And more down south...
If you are cool with flying then try booking your flights well in advance when you see specials, you should be able to get from Syd to Melb for very cheap with Virgin Blue.

As people tell you Flying is by far the cheapest but what do you see. Hiring a campervan is the way to go http://www.wickedcampers.com.au/ This is you cheaper option or you may get a hot deal from Britz or Apollo but then you are limited for time. The trip is awesome and you can call into Airlie beach, gateway to the whitsunday island you can also bush camp on the way down just spend the night in the rest areas.

Check out http://www.wickedcampers.com.au/pricing/roadtrips-australia/sydney-to-cairns. The page has an itinerary for a 21 day road trip from Sydney to Cairns already planned out - you can just do it in reverse!

Car is the cheapest, then comes bus and then train. Rent a car, it's quite crazy how expensive buses and trains are, and you've got no comfort or freedom to stay where you want, and will have to sleep on the bus - i've done it once and i'll never do it again.

Flying is definitely cheaper and you can check the Virgin Blue website everyday from 12-1pm EST to see what specials they're offering that day. You can also check Regional Express, JetStar, Qantas and Tiger Airways for costs. Or go to this site, check the times and then book directly with the airline that suits you - http://www.webjet.com.au/flights/

That said, there's the tilt train from Cairns to Brisbane that's really quite nifty. That's about $300 one way and you'll get to see a bit more. Maybe stop off in whatever towns that interest you for a bit before continuing (though you'd have to book the different legs separately for that). Then once you get to Brisbane you can fly to Sydney or Melbourne.

I do not recommend driving that whole way. It's a bloody long way - almost 3,000kms to Melbourne, and that's only if you drive straight and don't go down the coastline (which is much prettier, and you'd want to see that).