The cathedral of Santa Maria Assunta sits at the top of the old town, opposite the Palazzo Ducale. The exterior is simple — pink stone, a rose window with the symbols of the Evangelists — but inside the single broad nave is covered by a remarkable system of pointed transverse arches, ten of them springing from the side walls like the ribs of an upturned boat. Built in the late 13th century, with a 16th-century apse. Among the works inside is a small Pietà attributed to Dono Doni.
Easy to combine with the Palazzo Ducale next door.