But some doors don't open because they front unrealized architectural visions, some of which are memorialized in Mark Osbaldeston's "Unbuilt Toronto: A History of the City That Might Have Been" (Dundurn, 2009).
R.C. Harris' proposed water tower for the St. Clair Reservoir is one such project. The only physical evidence of its existence is a concrete ring on the southern flank of the reservoir, near a new dog-walking area. I wrote about that water tower in The Toronto Star, here.