The above links in the thread have expired but I did see them yesterday.
Did a little bit of research on that end of Stephen Ave this morning (I love this stuff and am always fascinated by what used to exist in places. Maybe my new year's resolution will be to get back into exploring and taking photos of these places like I used to. Many of the photos posted below are by a woman named Alison Jackson who did the same thing in the 60s and 70s, just going around documenting Calgary's buildings)
Some photos of the Burns building showing what is now the SE corner of Olympic Plaza -
The following photo is described as "North side of 8th Avenue between 1st and 2nd Streets S.E." so would be exactly where Olympic Plaza is now.
Also, a photographer named Bill Simpkins took some street level photos of the area in the 70s which can be seen here if you go through them -
https://digitalcollections.ucalgary....=SearchResults
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I might as well share other photos of the surrounding area I came across while researching.
Some fella riding a Roman chariot. Glenbow would be on the left and the Convention Centre on the right -
The following 1958 photo is where the Convention Centre (Rossos/A&W/Centini) is now -
You can see more if you search Cameron Block on the Glenbow archives including the aftermath of a fire in 1961 in which seven people died and the building was destroyed.
And then on the other side of Macleod, you have the Municipal building sitting there cutting off through access. This is what used to be there in 1963, the north side of the 300 block of 8th Ave -