Australia is nearly as big as the continental US and has incredibly disparate landscapes; you can participate in nearly any type of adventure and fun activity: world-class diving, climbing, hiking, sky-diving, wine tastings, bush walks, camping and surfing are just a sampling of the sheer diversity in Oz. The culture is super-laid back, locals are friendly, and the backpacker community is warmly embracing of both newbies and old-hat travelers alike.