BAPTISTERY, that part of the church, or a special building in which is administered the sacrament of baptism. In the earliest ages of Christianity the solemn administration of this sacrament was reserved to the bishop, and to the Episcopal church was generally annexed a special building called the baptistery. As the converts to Christianity increased, it became necessary to set aside for the baptismal ceremonies a small space within the main building of the various parish churches. The large baptisteries were generally circular or polygonal in form and were placed close to the cathedral church. Many were noted for their beautiful architectural forms. Northern Italy contains many fine examples, notably at Pisa, Parma, Florence, Cremona, Lucca, Siena, Bologna, Ascoli and elsewhere. Many of these are large buildings capable of holding great throngs of people. About the time of the Renaissance separate baptisteries ceased to be erected, baptismal fonts within the church taking their place.