Rome's Tiber River has fallen to unusually low levels after weeks of dry weather, exposing the weathered stone pillars of an ancient bridge near the Vatican. The structure, traditionally known as Pons Neronis, or Nero's bridge, has emerged from the receding waters, offering a rare glimpse of the city's imperial past.
Archaeologists, however, caution that the bridge may not have been built by Nero at all. Antonella Bonini, an archaeologist with Rome's cultural heritage superintendence, explains that the bridge's traditional name may be misleading. "The bridge passes near the villa of Agrippina, the circus of Caligula and then the circus of Nero and traditionally takes the name of Nero, because objectively Nero is the most famous person linked to this area," she says. "The bridge, however, is considered by scholars to be older, built by Caligula, Nero's uncle, to connect the villa of Agrippina, who was Caligula's mother, on the other side, currently roughly corresponding to the Santo Spirito Hospital (near the Vatican). We assume that it already existed in 39 AD."
A relic of imperial engineering
The bridge's exact origins remain a matter of scholarly debate, but its presence underscores the engineering prowess of ancient Rome. Bonini notes that the structure was likely out of use by the late third or early fourth century. "In the registers of ancient Rome's neighbourhoods (Cataloghi Regionari), which list the most important monuments of Rome, drawn up between the Diocletian and Constantinian ages, this bridge is no longer mentioned," she says. "The Pons Aelius bridge is listed in its place—that is, the bridge that connects Castel Sant'Angelo, built by Emperor Hadrian to connect his mausoleum with the center of the city."
The reappearance of the ruins has drawn crowds of curious onlookers and history enthusiasts to the riverbanks, a rare moment of connection with the city's layered past. For many Romans, the sight is a poignant reminder of how climate and history intertwine.
Water crisis deepens across Italy
The low water levels are not merely a curiosity; they signal a broader environmental challenge. Giovanni Giganti, coordinator of Rome's Civil Protection centre for water management, reports that the Tiber's flow has dropped well below its historical average. "The Tiber is facing a rather important low-water phase," he says. "This is due to a series of factors, including the prolonged drought of these summer months. The average flow rate in the urban stretch of Rome has fallen below 80 cubic meters per second, against a historical value that is around 150 on average."
The crisis extends beyond the capital. Giganti points to a lack of snow in the Apennines as a key contributor. "We are facing a major water crisis," he explains. "It is a crisis that is also due to the fact that this winter we did have quite abundant rainfall, but then the dry periods were quite long. Another direct cause is the scarcity of snow on the Apennines."
Italy's water woes are part of a wider pattern affecting southern Europe, where rising temperatures and shifting precipitation patterns are putting increasing pressure on water resources. The situation has prompted calls for more robust water management and climate adaptation strategies across the continent.
For now, the exposed bridge serves as both a historical treasure and a stark symbol of the changing climate. As the Tiber's waters recede, they reveal not only the remnants of an empire but also the fragility of modern infrastructure in the face of environmental change.
