In Toronto in the 1950s they tore down some buildings in a swath running parallel to Bloor and Danforth, to put in the Bloor-Danforth Subway by digging a trench. So now there is a string of parking lots and tiny and hardly used neighbourhood parkettes runnning parallel to Bloor and Danforth along part of the length of the subway. You can see it here, for example - Logan Parkette, Carlaw Parkette and a string of parking lots and here (Oscar Ryan Lane, etc). Here's more of a street level view.

I once scouted out a long section to see if a bikeway on stilts would perhaps work running over those parking lots and parkettes, ie. running directly above the subway line, but it looked to me like there would be too many interruptions and diversions.

The alternate plan, which cycling advocates are pushing, is put separated bike lanes on Bloor or Danforth themselves.