The pentagonal tower is a fortress located at the beginning of the main street of Porech, Decumanus. Its current form dates back to 1447, and was erected under the reign of the pedestal Nicolo de Lion. His coat of arms with initials was engraved on the east upper side of the wall. The builder of this magnificent tower was Johannes de Paris, while his son Lazaro designed a lion relief where he engraved their names. This is the only example of a Venetian lion on the eastern Adriatic coast with engraved creator names. Archaeologists have determined that the tower was rebuilt and upgraded several times from the ancient to the medieval era. In front of the pentagonal tower stood another square shape. Along with the city gates, it was demolished in the 19th century after it lost its defensive function.