The baptistry is located underneath the eastern bays of the choir of the Duomo.
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The Florentines didn't spare any trouble or expense to decorate the baptistry.
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The baptistry at the west end contains a carved stone font with a carved oak cover.
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In those days, Falls Baptist Church didn't have indoor toilets, let alone a baptistry.
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But when the baptistry was built, this under-church was filled with rubble.
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It was replaced or altered by another early Christian baptistry in the sixth century.
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The exterior of the baptistry was reworked in Romanesque style between 1059 and 1128.
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He had bequeathed several relics and his great wealth to this baptistry.
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There is also a baptistry of the 5th to 7th centuries dedicated to St. John the Baptist.
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More examples
Baptismal font: bowl for baptismal water
In Christian architecture the baptistery or baptistry (Latin baptisterium, from Greek) is the separate centrally-planned structure surrounding the baptismal font. The baptistery may be incorporated within the body of a church or cathedral and be provided with an altar as a chapel. ...
The Baptistry of St. John (Battistero di San Giovanni) is a religious building in Pisa, Italy. It started construction in 1152, in replacement of an older baptistry, and completed in 1363. ...
A special room or area in the form a pool for baptizing in the ancient Church. Gradually it was replaced by the baptismal font (see kolymbethra).
The temple baptistry is used for proxy baptisms, living persons being baptized for and in behalf of deceased individuals who have lived through mortality without the opportunity of receiving this sacred ordinance.