A lot of people have asked about the old narrow gauge North Australia Railway (NAR) from Darwin to Birdum and how that relates to the newer Adelaide Darwin standard gauge route so o I have created a map of roughly of all Northern Territory routes and this is available via this Google Map and can be downloaded into Google Earth via the download button at the top.
The data is actually from OpenStreetMap (OSM) which means, if you know of an error or omission then feel free to update the base OSM map. The NAR OSM relationship is available here and the Ghan is here. The Ghan does not continue to the wharf.
If you are editing, then please keep in mind that 99% of the NAR should be defined as "abandoned" and that you should only really map what is visible on the ground. Thus the rail-trail takes higher precedence than the NAR (sorry).
I would be interested to hear what you think.