The collection of musical instruments, displayed in the Ptuj castle, is of national importance. Comprising some 300 instruments used for performing both art music and traditional music, it is the biggest such collection in Slovenia. A rarity of international fame is the Roman tibia from the 2nd or 3rd century. The collection is divided into thematic sections, representing the former Ptuj military band, more recent city brass band, as well as wind, string, plucked string and keyboard instruments. Exhibited are typical instruments which in the past were typical of the aristocratic, bourgeois and ecclesiastic life from the second half of the 17th century onwards, and were made by prominent instrument makers from Vienna, Graz and Prague, as well as by national masters.