If you are in Melbourne for a long or short stay you should make a visit to the "Old Melbourne Goal."
Experience what it was like to be arrested and held in jail. You get to see the different types of cells. The holding cells, the padded cell, the wet cell! You get locked in a cell with alot of people and the lights are turned out, a bit frightening for some but an authentic recreation of what it must have felt like to have all your freedom and rights taken away from you.
You can do a self guided tour of the Cell Block where there is a clear and informative written summary in the cells outlining the different criminals that stayed there. Be aware that you do need to be able bodied to move up and down the steep metal staircases in the cell block.
I was surprised to learn that the Police Station Watch House onlly closed its doors in 1994. Not so long ago.