Northern Light
Superstar
it effectively already goes to lakeshore. Extending it directly south would run it right through the Scadding Cabin as well, the oldest structure in the city.
It meets Lakeshore (via British Columbia Drive) at the western extreme of the Exhibition Grounds.
I do see connectivity value in creating a more direct, N-S to Lakeshore and Ontario Place.
The cabin is easily avoided.
But clearly, such a connection would run across some existing greenspace, and parking, and displace something.
You can go either of these two ways (roughly) to get to Lakeshore, while leaving Scadding where it is.
The eastern option cuts a bit closer to Scadding, but could be bumped further east, at the expense of the current park/public space design.
This route would likely displace the Fort Rouille Monument, unless you went east and over the fountain/bandshell area.
The western options cuts relatively to close to the Liberty complex. I tend to think the more westerly option would be less disruptive. The alignment could be closer to the Windmill than I suggest in the image above.
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I can't say I think the extension is a top priority pending a thoughtful discussion on the future of Exhibition Place.......and I hasten to add, does not need to be tied into the bridge project that is the subject of this thread.
But I think it is worth considering down the line.