Many conjectures have been made as to the exact location of the house where Galileo Galilei was born. Following the indication in the baptismal record, which indicated the parish of Sant’Andrea as the scientist’s birthplace, until the mid 19th century it was believed that the house was found near the little church of the Fortress, that is to say, Sant’Andrea in Chinzica. This conviction was so well-rooted that in 1864, on the occasion of celebrations for the third centennial of the birth of Galileo, a plaque was placed on the wall of the Fortress which read: «Here was born Galileo Galilei on February 18, 1564». Several important details, however, were not taken into account, first and foremost the fact that to be born inside the Fortress, one had to be the child of a soldier, which was not the case of Galileo.

The mention of the parish of Sant’Andrea, however, also led scholars to discard yet another hypothesis according to which the scientist was born in a house that his father Vincenzo Galilei had rented from the Bocca family for one year, starting from August 1563. "Located in Chiasso dei Mercanti", this house still belonged to the parish of San Michele; this evident contradiction with the fact supplied by the baptismal record combines with the fact that, according to archive documents, Galileo’s father rescinded the contract several months prior to its natural expiration.

The most likely solution to this historical "enigma" resides in the mistaken identification of the church referred to by the baptismal record. The parish of Sant’Andrea was indeed not that of the Chinzica quarter, but rather the homonymous church of Sant’Andrea Foris Portam, under the jurisdiction of which, was the house of Galileo’s mother, Giulia Ammannati, since the early 16th century. Scholars therefore agree in recognising Ammannati House, still visible on Via Giusti, as the birthplace of the famous Pisan.