Shags post from Poland reminded me of a very good website.
I may have posted this before, but I'll do it again.
www.thirdreichruins.com
The website is by Geoff Walden. I belive his father was in Germany during or right after the war. Geoff has gone back and taken photos of the same places (where possible). The site is loaded with hundreds of before and after photos.
It's a must see for anyone interested in history.