Finished in 313 and known as the Lateran Palace, the site served as the seat of the papacy following Emperor Constantine’s Edict of Milan that promoted religious tolerance of Christianity across the Empire.

Author: Italian Ministry of Culture;

Gennaro Sangiulliano, the Italian Minister of Culture, said "this is an extraordinarily important find for the city of Rome and its medieval history, as no extensive archaeological excavations have ever been carried out in the square in modern times".