Between 1140 and 1146, Guglielmo III Adelardi dei Marchesella had defensive structures built in Polesine, small but well-structured castles to protect his properties from the ambitions and plots of the Estensi. Of these ancient fortifications, only the castle of Arquà Polesine remains in Polesine, one of the most interesting and well-preserved medieval sites in the area. Only with the definitive passage to the Venetians in 1482 did the complex lose its defensive function and was transformed into a true noble residence, of which the frescoes depicting mythological scenes created between the second half of the 16th century and the beginning of the 17th are still visible today. Currently, the castle is owned by and is the seat of the Municipality of Arquà Polesine.
