Ruins of Centuries-Old Palace That Housed Dozens of Popes Discovered in Rome

Archaeologists in Rome have unearthed the medieval-era walls of a palace that housed the papacy for hundreds of years, between roughly the 4th and 14th centuries.

The site was found during infrastructural improvements in the Piazza San Giovanni in Laterano, which is slated to host the Catholic Jubilee, a major pilgrimage event, in 2025.

“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,” says the Italian Ministry of Culture in a statement, per a translation by Reuters’ Alessandro Parodi.

Researchers led by Daniela Porro, director of the ministry’s art history department, discovered walls that they believe were constructed as early as the ninth century, to protect the piazza’s monumental basilica and palace from raids by the Saracens (a medieval term for Muslims), as well as internal conflicts among Rome’s elite over the control of the papacy.

The piazza’s first papal estate was built after Constantine, the first Roman emperor to convert to Christianity, issued the Edict of Milan, a proclamation of religious tolerance, in 313. Known as the Lateran Palace, the site served as the seat of the papacy, gradually expanding its footprint in Rome until 1309, when the Holy See moved to Avignon, France, where it stayed for seven successive popes.

In 1377, Gregory XI returned the papacy to Rome. By then, the Lateran Palace had fallen into disrepair, damaged by fire, earthquakes and invasions. Instead, the papacy made its home at the Vatican, where it remains to this day.

With no further need to protect the Lateran Palace, the structure’s walls were demolished, buried and forgotten. According to Rome’s official tourism website, Pope Sixtus V ordered the palace’s reconstruction in the late 16th century, entrusting architect Domenico Fontana with the task. In the years that followed, the palace served as a hospice, an archive and a museum. It was also the site of the signing of the 1929 Lateran Treaty, in which Italy formally recognized Vatican City as an independent state under the Holy See’s sovereignty.

The discovery is likely to draw attention to the palace’s deep history—and potentially start a new chapter in this centuries-old tale. As Culture Minister Gennaro Sangiuliano says in the statement, the find testifies to the richness of Rome’s archaeological treasures, which must be protected as the city seeks to modernize.

Eli Wizevich | | READ MORE

Eli Wizevich is a reporting intern for Smithsonian. He studied history at the University of Chicago and previously wrote for the El Paso Times.