I don’t know where this pic have been taken and when (probably WW2), but it’s impressive… Look at the number of bombs released!
Maybe B29 carpet bombing japan in the closing stages of the war?
The pic displays that the photo was taken by AC 57687.
Following Classics hint, I searched for B29 57687 & found this:
I am reading the final chapter of Adolf Gallands: “The First and the last”, and there are no doubt that it could have been in Germany as well.
War is hell!
Gret found, Hiaw! 
Theres some very good photos on that link you provided Hiawatha.
I’m ashamed of my anorak at guessing the photo though :o
Came across this one and love it:
Two impressive pics indeed…the latter my new background.