The 1,700 year old Temple of Jupiter was converted into a baptistery in the 7th century. About 500 years later, a font was placed inside. It was large enough for total body immersion during the baptismal ceremony. This 12th century carving graces its front. Some historians believe the king on his throne represents Peter Krešimir IV the Great who rule Croatia from 1059 until 1075. Others believe it is successor, Demetrius Zvonimir. He was king until 1089.