Also:
http://www.thedambusters.org.uk/
I read a book about 617 Squadron, written decades ago. One of the folks involved (Guy Gibson?) wrote a letter to a friend of his, in which he said, among other things, “I have enclosed for your inspection the Mohne dam”.
He then had someone else (different handwriting) write on the envelope “Opened and contents removed by Wartime Censor”.
Actually, that prolly covers most of us .. LOL