A small pleasant city with 130,000 inhabitants, Cairns is an excellent point of departure for discovering the Great Barrier Reef (with Townsville more to the south). Treat yourself to a flight over the Great Barrier in a helicopter (it is less expensive to return in a boat). Do the rounds of the beginning of the century pubs in the centre of Townsville. Go to Magnetic Island from Townsville, and also to Hinchinbrook Island - the largest national island-park in Australia.