oooh I just remembered, the railway reminded me -- if you have the time (there's so much to cram into one trip)
A fantastic day trip, is to head out to Katoomba. The drive out to the Blue Mountains is amazing, and they really are blue, there was a scenic railway and a cable car type thing that gives you pretty impressive views of the three sisters, a rock formation
http://www.bluemts.com.au/tourist/th...reeSisters.asp
i don't remember if this was a coach tour or if I rented a car to go... but I know it was great.