Start / finish: place in front of the Johanniter Ordenskirche Length: 2.7 km Duration: 1 hour walking time Arrival: by car or by bus Condition of the paths: Sidewalks in one place Attractions: the Johanniter Ordenskirche the ruins of the Johanniterschloss The prison memorial and museum The town of Slonsk (Sonnenburg) is not only visited by connoisseurs of literature and Brandenburg history. Many come from Europe to the city that Fontane described in connection with St. John's Day in 1862 to commemorate the victims of the Sonnenburg concentration camp. Nature lovers and ornithologists are drawn to the Warta Estuary National Park not far from Sonnenburg, in the rift terrain between the Warta and the Sternberger Höhenland. The place, which arose on the border of the Knights Templar possession and a Slavic fishing settlement, is mentioned in a document in 1295. In the 15th century, the Order of St. John acquired the place and other places in the vicinity. In the 17th century, the newly built castle became the seat of the Brandenburg ballot and thus the master master of the order. The image of the place is shaped by today's Church of Our Lady from Czestochowa (Kosciół Matki Boskiej Częstochowskiej). The three-aisled hall church in which the knighthood of the Knights of St. John took place since 1550, was consecrated in 1508. In the interior, the late Gothic tendril painting of the vault in yellow and green tones with flowers in the middle is visible, which is interrupted in the central nave by the coats of arms of the 24 master masters since 1305 and ends above the organ choir with the coat of arms of the city of Sonnenburg. Another special feature of the church are the gilded keystones, which form a network in the vault and show images of saints, Madonnas or images of animals. The church got its present form after the town fire at the beginning of the 19th century. Not far from the church, in a half-timbered house that once housed a school, is now the home parlor. From 1834 to 1836 a Prussian royal penal institution was built in Sonnenburg, where from 1933 first the opponents of the Nazi government and later during the Second World War the resistance fighters from Europe were imprisoned. In memory of the victims of the concentration camp, a museum and memorial were built.