This is actually amazing. French Priest Fr. Patrick Desbois has made it his life's work to identify all the mass graves of murdered Jews in the Ukraine, in order to further Catholic-Jewish understanding. Read more, including a couple of articles about Fr. Desbois, here
Seriously, this has knocked me for six. A lot of this work is very risky, not least for the wounds they reveal. If you do, pray for this work.