In the comments thread on my main Union Station post, some have remarked about a mysterious, abandoned tunnel that links Union subway station to the railway station. Scott Haskill from the TTC sorted this one out for us, and the moment I saw the plans and one of the photos, I had an “aha” moment and remembered the connection.
Scott sent along a copy of the TTC’s plans for the station from 1953 modified at about the time the Royal Bank connection was underway (1977). The original tunnel appears on the City’s drawings for the existing retail level. If you compare the 1953 plan and the existing plan, you will see exactly where the abandoned tunnel is relative to the rest of the structure. Scott menioned that “there’s even a fire alarm plan in public view, mounted on the wall separating the GO concourse from the TTR part, near the McDonalds, that clearly shows the tunnel.”
Robert Lubinski sent me a photo taken by Lewis Swanson showing the Union subway connection in Nov 1955.
There is a page on the infiltration.org site describing this tunnel including a photo of its current state.