St. Mary's Cathedral (1130年) was rebuilt during the reign of Mariano II after being destroyed in a siege. Of the original structure of Mariano only parts of the apse and base of the campanile are left, as well as the Gothic Chapel of the Rimedio, which houses some medieval sculptures. Parts of a more ancient Byzantine edifice can be seen in the court. To the 17th century renovation belongs the Chapel of the Archivietto ("Chapel of the Small Archive"). The current Baroque style is largely from the 19th century restoration. (http://en.wikipedia.org/wiki/Oristano)