At a 15th-century palace that is steps from the Vatican and set to become a luxury hotel, archaeologists did what they always do in Rome, an ancient city thick with buried treasures.
They started to dig.
Rome is the gift that keeps on giving to archaeologists, though no one knew what would come from this preliminary exploration, a familiar routine at Italian building sites and development projects.
To the archaeologists’ surprise — and immense delight — the dig brought to light traces of a first-century theater that the team believes was built by Nero, the emperor with a now disputed reputation for tyranny, debauchery and a desire to indulge his inner artist. Although chronicled by Roman-era historians, the theater had never emerged from Rome’s archaeologically rich underbelly.
“It’s been stupendous, wonderful, amazing,” said Marzia Di Mento, the archaeologist who oversaw the dig at the palace, the Palazzo della Rovere. “It’s what every archaeologist would like to do.”
The archaeologists began uncovering walls — some with traces of stucco with gold-leaf decoration — that they hypothesize belonged to Nero’s private theater. The excavation has also turned up hundreds of artifacts that, though still being studied, have already shed new insight on life near the Vatican across centuries of Roman history.
Among the finds are small bronze amulets that pilgrims would have worn when trekking to Rome to see where St. Peter — one of the first leaders of the early Christian church — was buried, along with animal bones bored to make beads for rosaries. Both signal the presence of pilgrims, who grew in greater number as Christianity spread.
These artifacts can be added to others found in recent months through other excavations — both archaeological and preliminary work on construction projects. They include sundry statues, burial grounds, ancient thruways and traces of an ancient Roman road that may or may not be part of the legendary Appian Way.
The excavation of the palazzo garden, on the wide avenue that leads to St. Peter’s Basilica, began in 2020 before a large-scale renovation. One wing of the palazzo, which is owned by the Equestrian Order of the Holy Sepulchre of Jerusalem, is scheduled to open as a Four Seasons Hotel in time for the Vatican’s 2025 Jubilee, when millions of pilgrims are expected to visit Rome.
Leonardo Visconti di Modrone, the governor general of the order, told reporters on Wednesday that the rental fee from the hotel would help cover costs for many of its charitable activities in the Middle East, including schools and hospitals.
By law, building projects in Italy must be preceded by preliminary excavations to ensure that no damage is done to what is underground — a rule that some critics say creates a costly, time-consuming obstacle for construction projects, if it does not halt them altogether.
Alessio De Cristofaro, one of the archaeologists who oversaw the excavation on behalf of the city of Rome, described the dig at the palazzo as “a virtuous example where archaeology acts as a driving force to an important building renovation project.”
Once the artifacts from the site have been studied and restored, some of the best preserved will be showcased inside the hotel. They include rare fragments dating from around the 10th century, a period that left few remains to document because Rome was “in economic and demographic decline,” Ms. Di Mento said.
But it is the evidence of the first century that has caught many people’s attention. Nero built his theater in a pleasure garden that, according to historical texts, once belonged to his grandmother Agrippina and his uncle Caligula. The Roman chronicler Pliny the Elder, no fan of the emperor, described the theater as “large enough to satisfy even Nero’s desire to sing before a full house.”
Though uncertain about the building’s identification at first, Mr. De Cristofaro said that the high quality of some materials uncovered at the theater, including columns of rare African marble and gold leaf decoration, pointed to an imperial commission. Stamps on some bricks date the structure to the middle of the first century A.D.
“Archaeology works by hypothesis,” said Alessandro Viscogliosi, a professor of ancient architecture at La Sapienza University in Rome. Attributing the remains as belonging to Nero’s theater was “a reasonable” theory, he said, although it was “too soon” to know for sure because not much had emerged.
“If they continue digging, and we find the seats,” he said, “then we’ll be certain.”
Some recent scholarship has challenged Nero’s reputation for profligacy, suggesting that he was portrayed by ancient historians as a villain, accused of playing a lyre while Rome burned in A.D. 64.
“He was actually well loved by his people,” said Ernesto Migliacci, an author (with his father, Franco Migliacci, a writer of the Italian classic “Volare”) of a short-lived but highly entertaining rock opera about Nero that cast the emperor as a more nuanced antihero, thwarted from pursuing what his heart really desired: a life declaiming poetry and song.
Pelted with criticism because the stage had been built on the Palatine Hill overlooking the Colosseum, the show shut down after 11 days after nuns in a nearby convent complained about the music, Mr. Migliacci said. He accused historians who criticized Nero, like Tacitus, Suetonius and Cassius Dio, of creating politically motivated fake news.
After archaeologists finish their study, including mapping the site, the ancient structures will be reburied.
Covering it back up is the “best way to protect the site,” said Ms. Di Mento. Its story can be told through “other means,” including 3-D reconstructions, detailed maps created by drones and online material that will make the structure “more understandable, even to those who aren’t experts,” she said.
Then the artifacts that have been unearthed will need to be cataloged.
“It will take years to study everything,” Ms. Di Mento said.
