MSL Dunedin [2A]

It does seem like a long time but it was only in August that I posted the first article in the Dunedin series. There is now going to be a series of articles covering Mosgiel to Dunedin, starting from the Dunedin end, to link up with the Otago Central maps as they get completed back to Wingatui. Now using Retrolens, I can get detailed coverage of Dunedin from 1978-9. The ideal would be that it was from the 1960s or earlier, but 1978-9 is what is available at this time, and it’s very good stuff too, with a scales varying from 1:3000 to 1:8000 available. There is also a possibility of covering north of Dunedin to Port Chalmers in time, but that is not a priority at present.
The earlier article which has been retitled MSL Dunedin [1] showed the central city railyards and maps using the current Linz aerial coverage but not anything historical which I did not have at the time, so the first step is to overlay the Retrolens coverage onto present day Linz stuff and then work from there to map Dunedin as it was in the late 1970s. 
The maps will be especially interesting heading south from Dunedin where the motorway construction in the 1980s has changed so much through Caversham and that is with my typical map style of overlaying the historical onto the present and publishing both together, in this case I will set up the masks to show just the historic rail corridor over present aerials as well as publishing a separate map set showing the rail detail over the 2013 aerials. Included in this of course is documenting as far as possible the pre-1914 corridor through the single track tunnels. I have attempted to do this many times and the best conclusion is that this is more or less the route followed by the motorway through Caversham and in pre-motorway times it was just at the top of the cutting that the railway is in now, it was very close to the present corridor all the way where it actually deviated, which was past Caversham station, because a lot of the route from Dunedin to Caversham was simply regrading and doubling of the existing route as far as possible. It was mainly around the two tunnels that there was significant realignment and straightening because there were no stations in these sections, only at the ends of them.