The brick castle was built around the middle of the 14th century, certainly before 1361, when the teutonic officials residing at the castle were mentioned at that time. After the victory of Grunwald, the castle and the city were taken over without a fight by Jan Kretkowski, the starost of Radom. However, the Peace of Toruń concluded in 1411, turned Kurzętnik to the Teutonic Knights. The castle was heavily damaged during the Polish-Teutonic Hunger War in 1414. During the Thirteen Years War in 1454, the mercenaries on the side of the Teutonic Knights, fighting under the command of Ulrich von Kinsberg, captured castle and burnt it. The second Peace of Toruń in 1466 gave the damaged castle to Poland. Another destruction caused the Swedes in 1656. The buildings that had been decayed from that time were systematically dismantled.
The castle was built on a lofty hill. It consisted of main house situated in the southern part and an adjacent courtyard surrounded by a defensive wall. The site was 25×28 m. The castle courtyard from the north was closed by the chapel of Holy Cross. In the north there was a trapezoidal outer bailey with a length of about 60m. A rectangular, tower house measuring 8x13m rose from its short northern curtain. At the longer sections of the walls two defensive towers were placed. The main entrance, preceded by a drawbridge over a dry moat, was from the south. Expansion at the turn of the 14th and 15th centuries liquidated the inner courtyard of the upper castle. It also received an external defensive wall from the south. The castle was built mainly of glacial erratic stones, the bricks were used only to a limited extent.
Until today only partial walls and foundations have been preserved. Admission to the castle area is free.
Leksykon zamków w Polsce, L.Kajzer, S.Kołodziejski, J.Salm, Warszawa 2003.