The Battistero degli Ortodossi is the most ancient of Ravenna's monuments, dating from the late 4th to early 5th centuries. The dome of the baptistery has fantastic mosaics depicting Christ being baptized by John the Baptist, the group of apostles preparing for the baptism, and the heavenly paradise. In addition to mosaics, the interior holds the bronze cross from 688, the original marble ambo of the baptistery, and a 5th century altar.

