The Babi Yar is a ravine outside the Ukrainian capital of Kiev and a site of the most notorious massacre of Jews of the Soviet Union, where 33,771 Jews were killed in a single operation on September 29–30, 1941 in retaliation for guerilla attacks against German troops.
Men, women and children were forced to march, place all of their belongings in a pile, and were shot at the edge of the ravine. Bodies were laid in rows and piled on top of each other.
This act of genocide was considered to be the largest single massacre in the history of the Holocaust.
Photos from the Babi Yar genocide can be found at the following site http://www.holocaustresearchproject.org/einsatz/babiyargal/index.html