I thumbed up Richard's post for the Summerhill reference, not the Guildwood one.Where to begin..
You cannot put a train on top of the existing train shed without extensive modifications. With all the work recently done, I can't see that happening given the cost and disruption.
Also.. how would you build anything elevated in the downtown core without knocking down some buildings? I can't see property owners being ok with that.
Honestly, the best option would be to route it to Summerhill or build new terminals for it at Guildwood where VIA already stops.
If this train is heading for Peterborough next, then stations along the CP North Toronto and Belleville subdivisions make a lot of sense. For those claiming that the service wouldn't work if it doesn't go direct to Union, well, Porter Airlines doesn't fly direct to Union either, and it seems to have garnered a loyal following.
If we can get CP freight rail diverted around the north of the city paralleling the CN line (not easily done, I know), and make the modifications needed to the North Toronto subdivision and subdivisions connected to it, then candidates for stops are close to Agincourt on the GO Stouffville line, a one-stop extension to the Ontario Line 3 at Don Mills Road, Yonge Line 1 at Summerhill, University Line 1 at Dupont, the Barrie GO line, then build a new link to the Kitchener corridor to connect Alto to Pearson and points west. Anything at Union is going to be just as difficult with the increased rail traffic headed its way. Let's take over more tracks through this city for passengers, and move the freight around it that does not need to go through it.
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