During Roman rule in the area of Poreč, in the 3rd century the first bishop of Poreč, Bishop Mavar, was a victim of one of the Christian persecutions.  After a cruel martyr's death, the Bishop was declared a saint and the City's patron. Since then and until the present day Poreč has maintained its status as a diocese.  In the 4th century an early Christian cathedral was built at the place where Bishop Mavar suffered his martyrdom.  One hundred years later it was renovated and in the 6th century Bishop Euphrasius ordered the construction of a basilica - this basilica is today considered a famous building and is a true architectural treasure.  Since 1998 it has been an UNESCO protected site.