This defense tower was built in the 12th-13th centuries. It is the only one of the many once existing in the acropolis left intact, as the others were either demolished or incorporated into adjacent buildings. It is 46 m tall and can be seen from various parts of the city. It once belonged to the Oddi family, then passed on to the Sciri in the 16th century, hence its current name. It is also known as "Torre degli Scalzi" due to its closeness to the church by the same name.