The Palazzo Caetani was built in the 16th Century for Alessandro Mattei. It was the property of the Negroni in the 17th Century and then the Durazzo family, before eventually passing to the Caetani (the dukes of Sermoneta and princes of Teano). The palace has 3 floors and the façade is late Renaissance. There are 2 inner courts. One surrounded by columns and great pillars and the other contains a fountain which is made from a sarcophagus and ancient sculptures.