The castle of the bishops of Włocławek was built on the site of a hillfort destroyed by the Teutonic Knights in the 30s of the 14th century. It was built on the initiative of bishop Maciej of Gołańcza and was expanded by his successors until the first half of the sixteenth century. In the period preceding the great war of Poland with the Teutonic Order it was used several times for negotiations with the teutonic Grand Masters. It was staying here, among others, king Władysław Jagiełło talking with the Teutonic Knights about the return of the Dobrzyń region. In the years 1582-1600 bishop Hieronim Rozdrażewski transformed it into a defensive late renaissance residence. Destruction of the building took place in the second half of the 17th century. Eventually it was demolished in the first half of the 18th century to build a new palace.
The castle was located on a high slope, which gave it natural defensive values. First was erected brick, three-storey, single-bay residential house measuring 12×25 meters, later expanded by bishop Zbylut from Gołańcza to the size of 17×25 meters. From its western corners, the perimeter wall was running along the edge of the headland. In the southern part of the castle, economic buildings were added, and in the south-west corner quadrilateral tower. Reconstruction from the end of the sixteenth century consisted in transforming the interiors, the erection of the half-timbered house of the starost and the free-standing gate tower, on a dry moat separating the castle from the lower part.
After archaeological and architectural research in 1978-1985 the castle was secured in the form of a ruin.
Leksykon zamków w Polsce, L.Kajzer, S.Kołodziejski, J.Salm, Warszawa 2003.