Dietrich von Groningen , master of the Order, began the first Castellum – type castle construction in the 13th century (Ordensburg Hasenpoth). At the beginning , the castle had a courtyard, corner towers and wooden buildings in the courtyard. It served as proctective border zone where the territory of Courland bishop and the Livonian Order met. In the 15th century , living quarters were built, including cellars and a gallery. Above the gates in the courtyard, the plastering has partially survived with its decorative finish in the scgrafito technique.