January 27th, the anniversary of the Soviet liberation of Auschwitz, is the day marked by the United Nations to remember the Holocaust. Observed at the UN headquarters and in countries throughout the world, International Holocaust Remembrance Day is not the only memorial day. Some countries observe a date that relates directly to their own Holocaust history. Jews throughout the world mark the 27th of Nissan in the Hebrew calendar, a date just after Passover and in proximity to the Warsaw Ghetto Uprising of 1943 to remember these catastrophic events.