I took a walk to Union Station today and did some research on the internet to find out where the entrances to the tunnels were in relation to what Union looks like now.
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So, based off these two old floor plans, the blue arrow is where the entrance to the tunnel to Royal York was, you can see stairs (down to the tunnel) marked on the floor plan.
This is a photo from today with a blue line on the floor where the entrance was, and a photo from way back when in this thread, with a blue line on the floor where the entrance was. You can see the railings match on the photos within the red circles.
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This is a photo from today of where I think the entrance to the tunnel to the subway was based on the floor plans (on the floor plans I marked the tunnel remnant in yellow on the newer floor plan, with a yellow arrow pointing to the entrance). It's marked with a yellow line in this photo. Correct me if I am wrong.
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