The Lateran Baptistery (San Giovanni in Fonte) was built in the early 4th century, which makes it the oldest baptistery in the world. Its octagonal design (eight is a symbol of immortality) was copied in numerous baptisteries.
The eight porphyry columns in the interior were erected by Pope Sixtus III (r. 432-40). They support an architrave, which, in turn, supports eight smaller marble columns. The gilded and painted wooden ceiling dates back to the pontificate of Pope Urban VIII (r. 1623-44).
The Chapel of St Venantius was added by Pope John IV (r. 640-42) in 640. Its apse is decorated with mosaics (642-49) commissioned by his successor, Pope Theodore I (r. 642-49).
Blogging about Rome:
its art, history and culture.
My name is David Lown and I am an art historian from Cambridge, England. Since 2001 I have lived in Italy, where I run private and
small-group walking tours
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