Symbol of the city, the Ferrara Castle is situated in the center of the historic urban core, hub between the medieval part and the fifteenth expansion designed by the architect Biagio Rossetti. Until the early thirteenth century, in this area an ancient watchtower existed next to the door of the Lions that opened to the north. In the mid-fourteenth century, the Este family, who became lords of Ferrara, concentrated their building and properties in this urban sector, transforming the tower into a small fortress. After a serious revolt in 1385 that inhabitants of Ferrara had opposed the ruling family, the Marquis Nicholas II decided to completely renovate the fortress, giving rise to a new castle called San Michele, designed by Bartolino Ploti (or Bartolino from Novara), one of the best fortifications designer of the era. The result was a massive structure, with a square plan with four square towers at the corners, all surrounded by a wide moat. The primitive tower of the Lions had added the towers of St. Catherine, St. Paul and Marchioness, of the same size and height, divided into three floors. The towers were later connected with large parts of two floors building, acts to constitute a veritable fortress, internally open around a big courtyard characterized by a fifteenth-century loggia. The stands of the second floor of the factory buildings, and those of the third floor of the towers, were defended by crenellations projecting on corbels, according to the most traditional war architecture formulas of the era. Outside, the tapered base came up to the string course of the ground floor, marked by a stone curb, mainly with a twisted ends decorated with badges from the signs of the Estensi family. The access was through two drawbridges protected by a rampart and smaller towers, connected to the outer bank of the moat by other bridges.

From the second half of the fifteenth century, the Castle evolved into a residential palace. In the second half of the sixteenth century the restoration of Girolamo da Carpi, the architect Alberto Schiatti and finally Pirro Logorio, introduced those elements, such as the marble balustrades and Renaissance shrines above the towers, which are still one of the defining aspects. Especially the interior was enriched with paintings, furniture and works of art, unfortunately largely lost: a real decorative program, developed throughout the sixteenth century, to which they were called to work the greatest artists of the time. This Castle became the driving force of the “Ferrara workshop“, workshop of art and civilizations, direct expression of refined Estensi court.