Ptuj Castle occupies a site overlooking Ptuj town centre, where there have been fortifications since the ninth century. The castle was begun in the 12th century but extensive additions during the Renaissance and Baroque periods contributed to the way it looks today. The castle houses the majority of the regional museum collection (there is more at nearby Ormoz castle). The collection includes exhibitions of musical instruments, arms and armour, paintings, furniture and a special display of carnival costumes from nearby villages. There is a charge for the museum but the grounds can be explored free of charge.