disused platforms?

["Matt Dunn" <md3474@ozemail.com.au>]

i've only just discovered this group, along with my reasonably newfound
desire to know the history of the sydney suburban rail system. why? i have
no idea. it's never interested me before, but the more i use it the more i
want to know. so please forgive me if i touch on anything that's been asked
before or if i use the wrong terminology ... i'm a bit of a newbie at this!

first question: what were the tunnels behind platform 10 at redfern station
intended for and how long have they been there in that state?

second question: i get on and off at st. peters every day to go to and from
work in george street, right next door to town hall station. what was the
purpose of the island platform across from platform 1 at st. peters and what
appears to be a disused platform further along at erskineville station? all
the way along almost to the area just behind macdonaldtown station, there
seems to be a space where a line of some description once ran, along with a
handful of what appear to be blocked tunnels and former bridges over roads.
can anyway tell me what these were about???

thanks for your indulgence. i'm sure i'll find plenty more to ask about.

matt.