An important point on the tourist map of Słońsk is the Museum of Martyrdom, located at ul. 3 Lutego ‘54. The exhibition presents the history of a Nazi prison and a concentration camp functioning here under the rule of Hilter’s Germany. The visitors may be surprised to see some unusual biographies of prisoners held here, e.g. a Nobel Peace Prize winner, Carl von Ossietzky, a journalist from Hamburg. As an outstanding humanist and proponent of peaceful solutions he was controversial to the Nazis and in 1933, he was arrested. His imprisonment provoked international outrage. For his achievements, von Ossietzky received the Nobel Peace Prize in 1935. His personal collection of the prize was prevented by the authorities of the Third Reich.
In 2015, renovation and modernization works were completed, and the museum was enriched with a multimedia exhibition, giving it a new, more attractive form. Admission to the museum is free. Visitors are invited from Wednesday to Sunday, 11.00 am- 04.00 pm.