Back in the early 2000's I started videotaping (yes, we used tape back then) some of my explorations of various abandoned industrial sites in and around Toronto. I eventually made a film called Echoes of Forgotten Places, it may be one of the earliest documentaries on the subject.
It's available once again on DVD region 0:
https://waveshaper.shop/products/echoes-dvd
The trailer is still on youtube:
It's available once again on DVD region 0:
https://waveshaper.shop/products/echoes-dvd
The trailer is still on youtube: