The first stronghold of the Teutonic Order on the left bank of the Vistula, the Castle was built in the late 13th century and is a massive multistorey brick structure with a deep courtyard. In 1464 it came under Polish rule and remained so until the First Partition of 1773. The Prussians remodelled it to accommodate a barracks, a jail and an ammunition depot. It was seriously burnt out in 1921, but the 2m-thick walls survived and it was later restored.

The castle now houses the Archaeological Museum.