Made this map of a possible line along the 407 railway corridor. I call it the North Toronto Line and would essentially be a cross region route connecting Durham, York, Peel, Halton, and Hamilton as well as every GO Line. Since the line crosses multiple boundaries and is so long it would be part of the GO network. What rolling stock it would use would be up for debate as I have seen some on here propose such a line use OL rolling stock and not GO EMU stock. I also included the Bolton and Midtown lines to show where a connection to them would be made if they were to be created before or after this line would be.
I view this line as being Toronto's version of the Musashino Line in Tokyo. It to is a long line that wraps around the northern periphery of the city connecting the various suburban communities outside of the core. It also connects various rail lines sprawling out of the city together in the suburbs and utilizes the JR Freight main line which freight trains use to get around the city since they are not allowed into the core anymore.
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