The Ethnographic Museum of Sicily, named after Giuseppe Pitrè, is located in one of the Palace's guesthouse.

The building was designed in 1799 by the architect Giuseppe Venanzio Marvuglia on commission by the King Ferdinand III of Sicily.

On the first floor, there is the entry hall, a small office, a dining room (with a "magical" table) and the King's bedroom.

The Queen's floor is entirely surrounded by an open-air terrace giving a view of the gardens, accessible either from the interior or from two external circular staircases.

The building is decorated with paintings and frescoes of Giuseppe Velazquez, Vincenzo Riolo, and other artists.