Mentioned for the first time in a document dated 976 and subsequently in 1037 as property of the powerful Convent of San Giovanni Evangelista in Ravenna, the construction of the Polenta castle should date back to the 10th century, when all the villages in the Romagna territory that held a position of relief were fortified with the construction of a city wall and a fortress, which became the seat of the local lord.
However, there is no certain information on the Da Polenta family until the 12th century. It seems to be a family of local farmers who first became milites, that is, soldiers placed to guard the castle owned by the Ravenna monastery. The social and political climb of the Da Polenta family began in 1182: in that year Guido's sons, Lamberto and Geremia, asked the abbot of the Monastery to obtain the castle of Polenta in emphyteusis until the third generation, for the rent of 5 sous of Venice. The request was granted.
The fortress, located on the top of the hill, had a quadrangular plan, with the sides oriented along the east-west and north-south directions. Walls and towers, built in local stone, rested on the living rock of the hill. An imposing tower stood on the north-eastern corner of the city walls. To defend the south-eastern corner there was a more modest circular tower. The eastern side was closed by a two-storey building, which was the home of the lords of the castle. On the southern side, where the land had a gentler slope, there was the entrance to the fortress: a rectangular opening at the base of a tower which, for safety reasons, allowed only one visitor to pass through on foot or on horseback at a time.
Much of the fortress remained intact until the beginning of the nineteenth century, when the new owners demolished the walls and towers to obtain building material. At the end of the 19th century the few remaining ruins were used as a farmhouse by farmers and plasterers. At the beginning of the twentieth century, following a fire, the eastern part of the building was destroyed and then completely demolished. The entrance tower collapsed after the Second World War.