A Stolperstein (from German, "stumbling block"; plural Stolpersteine) is a monument created by Gunter Demnig which commemorates a victim of the Holocaust. Stolpersteine are small, cobblestone-sized memorials for an individual victim of Nazism. They commemorate individuals – both those who died and survivors – who were consigned by the Nazis to prisons, euthanasia facilities, sterilization clinics, concentration camps, and extermination camps, as well as those who responded to persecution by emigrating or committing suicide.
While the vast majority of stolpersteine commemorate Jewish victims of the Holocaust, others have been placed for Sinti and Romani people (also called gypsies), homosexuals, Jehovah's Witnesses, black people, Christians (both Protestants and Catholics) opposed to the Nazis, members of the Communist Party and the Resistance, military deserters, and the physically and mentally disabled.
The list of places that have stolpersteine now extends to several countries and hundreds of cities and towns.