Ottawa from the Air in this photo dated to September of 1955.
You can see a lot of the old city in this one, including the Eddy Plant, the Printing Bureau on Nepean Point, the temporary buildings on Sussex, Elgin and Wellington, etc.
There's quite a few buildings where Confederation Park and the NAC are now, but if you look along Slater and Albert half of downtown seems to be a parking lot!
(Photo: Harold Mayer, University of Wisconsin Milwaukee catw-5248)