Of the Baptistery - which once constituted one of the Early Christian architectural elements together with the cathedral, the bell tower and the martyrium - are today only a few remnants from the primitive construction of the 7th century in front of the Cathedral of Santa Maria Assunta in Torcello. It is believed that building held a basin of blessedwater that gushed from the mouths of symbolic animals. Some scholars believed that the building was related to the nearby church of Santa Fosca while more in-depth and recent studies have connected the building of the Baptistery to the same period as the building of the church dedicated to Santa Maria Assunta.
Numerous researchers have hypothesized as to what shape the original site plan could have been for some time, but onlythe excavations carried out at the end of the 1800s definitively solved the mystery, establishing that the original planwas of circular form, as we see it today. It had two entrances, one at the front of the church and the other to the side, between two large semi-circular terracotta niches which still exist today.
Thanks to the research carried out by Prof. Maurizia Vecchi - reported in her book Torcello. Research and contributions - the discovery of two important manuscripts dating back to different centuries showed that there were tworeconstructions carried out on building after the original building work, and not just one, as was previouslyhypothesized. In particular, a 1736 manuscript found at the Patriarchal Archive of Venice pointed out the structuralelements of the monument, specifying that it had a polygonal base which was rebuilt over an existing construction; subsequently, a manuscript of the Museo Correr of the early 19th century described an octagonal-shaped structure.