Blue Mountains
A regular train from central Sydney takes you inland to the Blue Mountains. It's not an area of high summits, more plateaus divided by river valleys which have cut steep cliffs into the shale and limestone. The forest is dense and populated with eucalyptus, which gives off oily particles giving the air a blue haze. The cliffs provide plenty of viewpoints, and a century ago, locals carved out various sets of steps into them to provide tourists with access to some of the dramatic waterfalls pouring over the edges.