Battistero Lateranense, Rome

The Battistero Lateranense is a Catholic baptistery in Rome. It is dedicated to Saint John the Baptist. This early Christian building became a pattern for medieval baptisteries throughout Christian Europe.

Its separate structure was later connected to the Lateran basilica by added construction. Within, a domed octagonal space gathers around a broad font designed for baptism by full immersion. Notice the porphyry colonnade around the basin: marble Corinthian capitals carry an entablature shaped in the vocabulary of ancient Rome.

For generations, this was Rome’s only baptistery, and its form spread through Italy; manuscripts even transformed it into an image known as the Fountain of Life. Pope Sixtus the Third founded the building in four hundred and forty. A later legend links Constantine the Great with baptism here, though the more likely location for his baptism lies in the empire’s eastern territories.

Under Urban the Eighth, Bernini reshaped the interior, while Andrea Sacchi painted episodes from Constantine’s life along the encircling passage. Borromini later added a carved exterior frieze bearing the heraldic arms of Alexander the Seventh.