Are Adelaide train tracks really open for the general public to walk along as portrayed in this film?
In Sydney, the only access to trains is directly onto the train station. The entire length of the suburban train tracks between stations are fenced off so people can't get to the tracks for security/safety/vandalism/liability reasons.
Yes, some of them are open. The stations are fenced off to a degree but you can access the tracks at certain locations.
shareSydney is actually the 'odd one out' in terms of railway security in the modern era. Up until the mid 70's all railway lines were fenced off, but around that time the fencing was all removed as a "beautificaiton" project. And yes, death tolls did sharply increase around that time, and have stayed raised ever since.
That's not to say that railway fencing was particularly reliable though; most of it was just old, otherwise worn-out rail shoved in the ground and intermixed swith wodden poles, then with barbed wire stapled to the top and four regular wires below.
I live in Adelaide and know the Outer Harbor line well (where the film was shot). And yes, the line can be accessed at particular points apart from at stations. Very different from Sydney. I've heard there are very few level crossings there - you either go over or under the rail lines! I guess that makes sense - can you imagine the traffic?!
However, the freight line is separate from the passenger line now. They created a freight bridge across the Port River, and the two lines don't really go near each other anymore. This film was made before that bridge was built.
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"I'm worth twelve of you, Malfoy" - Neville Longbottom