On the subject of stuff that's been torn down or generally made worse, I saw these two pictures on a blog:
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These are gates to a base along Gottingen Street in Halifax. Originally the gates lined up with the entrance to the Wellington Barracks, a complex with a few different buildings that enclosed a parade square. Sometime around WWII the barracks were partly torn down (at least one of the old buildings still remains) and replaced with a nondescript brick building that covered up the gate entrance.
The little plaques on the gates commemorate historical battles of the late 19th century, e.g. battles in the North-West Rebellion.
One of the original 1850's Wellington Barracks structures. This was a major garrison back in that era, a linchpin in the defence of a good chunk of the British Empire. The British forces didn't hand over these facilities to Canada until the 20th century.
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