Probably due to the wet foundations water table, the wall on Słupia had construction arches visible in the lower segments, the bottom of which were supported on a stone foundation. The external face of the wall is vertical, while the inside has an offset, which used to be a shooting porch.

The Witches’ Tower is based on a semicircular wall protruding out of the line of the external wall. From the direction of the town, the rectangular part of the tower also stands out from the face of the wall; this side used to be open, but now it is currently completely enclosed in glass. The bottom storey was vaulted, while the three top ones have wooden ceilings. The Witches tower is currently crowned with a reconstructed cone copula, cut off from the direction of old town. The east facade has several narrow rectangular openings located on three storeys.

In the 17^th Century, this tower was adapted to the purposes of a prison for women suspected of witchcraft – thus the origin of the name. According to available archives, 18 women were executed here. The first witchcraft process took place in 1651. Its victims were the ladies-in-waiting if the Duchess Anna de Croy – Scholastyka and Runga. The last victim of the holy ??? inquisition was a servant from Rowy – Anna Kosbad. She was put to death in 1714. The Słupsk literature and legends include Trina Papisten (Kathrin Zimmermann), who was burned on a pile in 1701.

In the 19^th Century, the tower was made into a storehouse. In the 20^th Century, it was a residence. In March 1945, the building was partially burned down by the Russian army. The Witches’ Tower was reconstructed and adapted to the purposes of an art gallery in 1975. The building is one of the oldest architectural monuments in Słupsk.

The Witches’ Tower Gallery was founded in 1976. It was the first gallery of the newly-founded Art Exhibitionion Office (the current BGSW). The gallery is three storeys high. The exhibitionion area is 86 m². The gallery hosts paintings, photography, small sculptures, graphics, drawings and spatial installation exhibitions.