The Palace of the Grand Master is probably the most iconic monument of the Hospitaller period in Rhodes. During its comprehensive restoration in the 1930s, it acquired its present internal layout as the administrative headquarters and residence of the Italian governor during the period of the Italian occupation of the island. In the apartments of the first floor the visitor may admire the ancient mosaic floors installed there by the Italians but originally derived from secular and ecclesiastical monuments excavated in the island of Kosι. Apart from the spectacular mosaics, there are also antique columns and capitals, medieval furniture, mirrors and paintings, candelabra and other objects complementing the decoration of the imposing edifice.

The permanent exhibition "Rhodes from the 4th c. AD to its Capture by the Ottoman Turks (1522)" is housed in a sequence of rooms on the ground floor. It contains representative finds of alll kinds from archaeological excavations in the Medieval Town (pottery, sculptures, detached murals, portable icons, implements, small finds etc.)

Another permanent exhibition occupying part of the ground floor and the basement presents the ancient city of Rhodes through the archaeological finds from a half-century of excavation and scholarship on the subject.