The Gran Salone della Meridiana (Meridian Room) is one of the most imposing roofed rooms in Europe; its construction was begun between 1612 and 1615 but was hindered by structural problems and was only completed in 1804. Between 1790 and 1793 the astronomer Giuseppe Casella thought of installing an Astronomic Observatory in the room but the only part of his design to be built was the solar meridian that gives it its name.
The collection, arranged in chronological order, contains some of the most important finds from the cemetery of Parthenope, the first Rhodian or more probably Cuman settlement situated on the hill of Pizzofalcone - which was occupied from the mid-seventh century to the mid-sixth century BC - and from Greek and Roman Naples, a colony founded by Athens and Syracuse with the support of Pithecusae between the end of the sixth and the beginning of the fifth century BC, an area which coincides with the old town centre of Naples.
The Medagliere (Medal Showcase) contains materials which cover an extremely large chronological range, from the first coins struck in Magna Graecia to coins of the Kingdom of the two Sicilies. The coins have been obtained by the museum both due to the acquisition of private collections and due to excavations conducted in the Vesuvian area and southern Italy.