The Castle Chapel

The Chapel of Saint Catherine of Alexandria has medieval origins, although its furnishings are mainly Rococo. In 1392, Bishop Henryk Sorbom established a chantry at the high altar. Initially there was only one altar; two side altars were added later through further endowments.

Bishop Adam Stanisław Grabowski commissioned new furnishings between 1751 and 1760. Altars, paintings and the organ case complemented the older Gothic structure. The combination of decorative furnishings and ribbed vaulting results from this remodelling, rather than all parts of the interior having been created at once.

Paintings from 1755 depict scenes from the Old Testament. They include the Sacrifice of Isaac, Rebecca at the Well, Jacob's Ladder and Joseph interpreting Pharaoh's dreams. The cycle also includes Joseph meeting his brothers. The decoration is attributed to Józef Korzeniewski.

Christoph Heinrich Obuch built the organ in 1760. Its carved and gilded case was made in Christian Bernard Schmidt's workshop in Reszel in 1760–1761. The instrument and its setting are the work of different craftsmen: an organ builder responsible for the sound, and a sculpture workshop producing the decoration.