Hello,

 
I'm writing to in regards to obtaining some information on Spencer Street subway,

When was the subway closed and why?

The mail train that ran under Spencer Street to the mail exchange did it continue down Bourke Street to the GPO on Elizabeth Street or is this a myth?

Any information would be greatly appreciated.

The last public bits of subway closed in 2005 as part of the redevelopment of Spencer Street subway.

More on the history of it can be found in this thread from 2009:
http://www.railpage.com.au/f-p1275998.htm

If you still have questions after looking at that, feel free shout out.