Montreal aerial befores-and-afters

Street map overlay by emdx

Seeing 1948 Montreal from above has been a bit of a trip. Ever since the aerial image archive of Montreal was posted online, it has posed more questions  than it has answered. My brain has been twisted and turned into pretzels by hours of trying to see exactly what has changed and how and why. The old Chaboillez Square is pictured above, showing the differences between 1948 and 2012. The historic spot sat near the trains on the east end of the Griff. By 1948 the trains were still there (just to the left outside the image frame) but the square itself wasn't even really a square and there was a giant triangle intersection beneath it which doesn't come with any explanation. If someone has knowledge of what that was about, please share it herein.
    Also, here's another before-and-after, it's the noose section of Redpath Crescent with new properties superimposed in the third image to show how much it has been built up.
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