Thank you Larry. I would add that, from time to time, certain things are published (color photos thought lost) or 4 tons of Luftwaffe aerial recon photos were found in a barn by the British, and are becoming available.
Off topic a bit, but I make it a point to note such sudden discoveries of various things. There are cases of documents being found in various locations that appear - appear - to have been used as bargaining chips upon surrender. Sort of a 'don't prosecute me and I will hand over the documents.' If the reverse happens, the documents remain lost. In at least one case, incriminating documents were carefully packed, surrounded by explosives and flammable liquids, and connected to tripwires. The question the reader of the following should ask is, Why do this in this particular case?
https://www.archives.gov/publication...techovice.html