On the basis of a field study, archeological excavations carried out in the years 1966-1967, and some earlier findings in this area (pottery, iron items – arrowheads, ferrules, a chisel), it was determined that the settlement in Słupsk must have already existed in the 9^th – 12^th Centuries. The community occupied a conical elevation in the area delimited by the following present-day streets – Partyzantów from the south-west; Kościelna and Garncarska from the south; and Henryka Pobożnego from the east. Its environs, however, would look different at the time – the settlement was located on an island created by the former arms of the Słupia but, because it got flooded by the river from time to time, an artificial conical hillock was banked up, measuring about 50 m in diameter, on which a fortification was erected. It was surrounded by a wooden/earth embankment and reinforced with a stone construction at its base. In written accounts the settlement in Słupsk was recorded, i.a., in 1248, 1269, and 1273. The so-called Old Castle, assumedly existing within the fortification, is said to have seen the birth of Prince Bogislaw X in 1454, who began the construction of the New Castle within the defensive walls, next to the Castle Mill.

St. Otto’s Church. The cornerstone was laid in 1872, and the consecration ceremony was held in 1873.