THE COLLECTION OF ARMS at Ptuj Castle is of national importance, as it comprises more than 500 pieces of various cold weapons, firearms, hunting and sporting weapons, and protective equipment dating from the 15th to the 20th centuries. Most of the exhibited items come from the nearby Vurberk Castle, while some pieces were collected by members of the Ptuj Museum Society.

Keyboard instruments
The oldest hammer action piano in this room is an instrument made by Karl Benedickt of Graz between 1785 and 1790. The piano by the great Viennese master Ferdinand Hofmann, made around 1795, also belongs to the golden age of Viennese classical music. To the left of them is an early 19th-century grand piano, one of the few surviving pianos made by Ignaz Bösendorfer, the founder of the famous Viennese workshop.
Since the end of the 18th century, 11 piano makers have been known in Slovenia, including master Andreas Wittenz of Ljubljana. His 1856 piano is a fine example of the Viennese school.
Player pianos are mechanical devices that automatically play melodies written on metallic rolls or on perforated paper. They were particularly popular from the second half of the 19th century until the Second World War. On the left is a Phonola, which attaches to the piano keys with wooden levers. On the right, you can see a piano automaton with mechanics already built into the piano body.