Pisa Baptistry in the context of "Leaning Tower of Pisa"

In Christian architecture the baptistery or baptistry (Old French baptisterie; Latin baptisterium; Greek βαπτιστήριον, 'bathing-place, baptistery', from βαπτίζειν, baptízein, 'to baptize') is the separate centrally planned structure surrounding the baptismal font. The baptistery may be incorporated within the body of a church or cathedral, and provided with an altar as a chapel. In the early Church, the catechumens were instructed and the sacrament of baptism was administered in the baptistery.

Pisa Cathedral (Italian: Duomo di Pisa), officially the Primatial Metropolitan Cathedral of the Assumption of Mary (Cattedrale Metropolitana Primaziale di Santa Maria Assunta), is a medieval Catholic cathedral dedicated to the Assumption of the Virgin Mary, in the Piazza dei Miracoli in Pisa, Italy, the oldest of the three structures in the plaza followed by the Pisa Baptistry and the Campanile known as the Leaning Tower of Pisa. The cathedral is a notable example of Romanesque architecture, in particular the style known as Pisan Romanesque. Consecrated in 1118, it is the seat of the Archbishop of Pisa. Construction began in 1064 and was completed in 1092. Additional enlargements and a new façade were built in the 12th century and the roof was replaced after damage from a fire in 1595.