Baptistry of Neon, reputed to be oldest monument remaining in Ravenna, it was partly erected on the site of a Roman bath. It is also known as
the Orthodox Baptistery to distinguish it from the Arian Baptistery constructed for the Ostrogothic King Theodoric some 50 years later.
The octagonal brick structure was erected by Bishop Ursus at the end of the 4th or beginning of the 5th century, as part of his great Basilica
(which was destroyed in 1734). The baptistry was finished by Bishop Neon at the end of the 5th century, at which time the mosaic decorations
were added. The original floor is now some 3 meters underground, so the proper structure and extent of the building can no longer be seen.
The octagonal design of the building, employed in virtually all Early Christian baptisteries, symbolizes the seven days of the week plus
the Day of the Resurrection and Eternal Life.