The Flickr Then and Now pool is a collection of photos comparing a place about 100 years ago to the same place today. I particularly like guil3433’s photos of Montreal. Two are shown here:

Bagg Mansion - Then and Now
The Robert Stanley Bagg mansion, Montreal 1900 and 2003

St. Denis and Ontario - Then and Now
Southeast corner of St. Denis and Ontario, Montreal 1894 and 2007

After a lot of confusion I finally figured out that there are two similar groups:

Some photos show up in both groups. Some don’t.

:: All Things Cool