One of the most important part of the palace in the Roman period was the site of Jupiter Temple. It was the most solemn place of all places in the palace, built for worshiping the greatest Roman God and Diocletian itself, considering he was the one who proclaimed himself as direct descendant.
The solemn role didn’t fain as it became the baptistery of the cathedral with the arrival of the Christianity in the 7th century. Today it contains the copy of the medieval basin that has the first inscription of the Croatian kings and the modern, bronze statue of John the Baptizer, done by Ivan Meštrović.
Among all the fabulous details of the temple, one of the most interesting is certainly the narrowest street in the town, officially called ‘’Let me trough’’, situated on the left side of the temple, right under the beheaded Thutmosis the III dynasty Egyptian sphinx, one of the two still existing in the palace.