​​Museum of Martyrdom, Slonsk​

​​Słońsk (named Sonnenburg until 1945) is a town with a remarkable, centuries-old history. One of the most painful chapters of its past were the years of the prison and concentration camp. During the Weimar Republic, Sonnenburg Prison served as a penitentiary for many political activists. After Hitler's seizure of power, it became the first German concentration camp where opponents of the Nazi regime were brutally repressed.

​The prisoners were mentally and physically abused and the place soon became known as ‘torture hell’. One of the most famous prisoners was Carl von Ossietzky, a German journalist, Nobel Peace Prize winner and opposition activist. After operating as a concentration camp for more than a year, the facility became a prison again and was a place of execution and suffering for opponents of the Nazi regime for years to come.

​The most tragic event took place on the night of 30 to 31 January 1945, when a detachment of SS men from Frankfurt/Oder carried out the mass execution of 819 prisoners. Among those murdered were representatives of many nationalities: French, Belgians, Germans, Dutch, Norwegians, Luxembourgers and others. The massacre began at around 22:00 and lasted all night. Ten people at a time were led out of their cells and shot between the prison wall and the workshop building. 

​In 1973, a small group of Słońsk residents decided to set up a museum and memorial to commemorate the victims of Sonnenburg and warn against a repetition of this terrible history. The official inauguration of the Museum of Martyrdom took place on 28 September 1974.

​The memory of the victims of these events is upheld not only by museum, but also through commemorative events organised by the municipality of Słońsk every year on the anniversary of the tragedy. The commemorative events are attended by prisoners' families, representatives of the authorities and delegations from Poland, Germany, Luxembourg and other countries whose citizens perished in Sonnenburg.

​The programme of commemorations includes: events at the Martyrdom Museum and cemetery of the victims of imprisonment in the Sonnenburg concentration camp and prison, a mass, and a meeting to develop a common historical culture of remembrance and European identity. These events are also an important element of German-Polish understanding and contribute to awakening interest in the history of the Second World War, especially among the younger generations.​