The duke’s Palace owes its name to the fact that, in the first half of the 17th century, it was residence of duke Alessandro Sforza of Segni, successively of the cardinals natural son, duke Francesco Sforza of Fiano and finally of duke Ludovico of Onano. Alberto Scoto had the central part built in 1292 and conceived as as law court . It was a highly prized building, as witnessed by the beautiful lancet arch one mullioned windows, framed by an elaborate fire brick decoration. The palace underwent several changes, among which the building of the fountain.