There is a website which holds records about known aircraft crash sites in Czechia since 1918. Unfortunately it's all in Czech but with a decent translator you can dig a lot out of it (base data even without). It contains information about known circumstances of each crash site, its location and if possible also an information about artifacts found on the crash site. It can be particularly interesting for everyone interested in WW2 air war or for someone whose relatives were airmen who died somewhere over Czechoslovakia.
This is the link to the website.
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