You may be thinking of "Union Station 2031 and Related Planning Studies" a Metrolinx Board presentation from 2011-11-23. It started with 6 initial options {Improve TTC/GO integration at Bloor/Dundas West & Danforth/Main; Add satellite stations @ Liberty, Bathurst, Cherry; North Toronto Sub with 4 stations; U-shaped downtown relief subway from Dundas West to Pape; GO Train tunnel under Queen St or King St; All Lakeshore GO trains underground between Exhibition and East Harbour} other ideas were added - a J-shaped relief subway and all Kitchener & Milton GO trains stopping at Bathurst or the Lakeshore tunnel going up under Osgoode & Queen stations. The following 2 options were investigated further.
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