Nero's Bridge Re-emerges from Tiber
The remains of an ancient Roman bridge have emerged from the Tiber River near Vatican City, offering a rare glimpse of a structure that is normally underwater. Large stone blocks of the crossing, commonly known as Nero's Bridge, became visible after weeks of dry weather caused the river's water level to fall, as reported by Travel Tomorrow.
The roughly 2,000-year-old bridge was last visible during another period of drought in 2022, according to the outlet. The bridge can be seen particularly well from Ponte Sant'Angelo, which crosses the Tiber beside Castel Sant'Angelo, although the sight could be temporary as water levels fluctuate.
The bridge is traditionally called Pons Neronis or Pons Neronianus, both meaning Nero's Bridge. However, archaeologists believe it may have been built before Emperor Nero came to power in 54 AD. One theory dates it to the reign of his uncle, Emperor Caligula, around 39 AD. Antonella Bonini, an archaeologist at Rome's cultural heritage superintendence, told Travel Tomorrow that scholars believe Caligula may have ordered the bridge's construction. The structure appears to have created a route towards the villa of Agrippina the Elder, Caligula's mother, and passed near the circus first associated with Caligula and later with Nero, which may explain why it eventually became known by Nero's name.
The crossing connected the ancient Campus Martius area on one side of the river with the area that later became Vatican City. The Circus of Nero once stood near the site of today's St Peter's Basilica, and according to Christian tradition, Saint Peter was martyred in the area. By the end of the third or beginning of the fourth century, the bridge was probably no longer in use and was absent from Roman registers, which listed Pons Aelius instead.
Water Shortage and Causes
The bridge's reappearance is not merely a curiosity but a sign of a serious water shortage, as Travel Tomorrow reports. The Tiber's flow has dropped below 80 cubic metres per second, while the historical average is around 150, according to Giovanni Giganti, Rome's civil protection coordinator for water management. The shortage has been linked to scorching temperatures, long dry spells after a rainy winter, and limited snowfall in the Apennine Mountains.
Modern waste items, including e-bikes, scooters, refrigerators, and a car, have also appeared in or around the river upstream, the outlet noted. The conditions that revealed the bridge point to a broader water crisis affecting Rome and other parts of Italy.
Wider Context: Droughts Exposing Ancient Sites
The reappearance of Nero's Bridge is part of a pattern of drought-driven archaeological exposures across Europe and Asia, as described by Jason Godfrey in The Star. In Spain, the Dolmen of Guadalperal, a circle of about 150 granite stones dated possibly to before 3000 BCE, has become visible due to drought. In 2022, the Yangtze River in China fell enough to expose Foyeliang Island, revealing three Buddha statues. In Serbia, receding Danube waters exposed wrecks of German warships sunk in 1944, some still loaded with explosives.
Godfrey wrote that the reason for these simultaneous exposures across different regions is clear: a warmer atmosphere holds more moisture and increases evaporation, causing faster soil and river drying. Higher temperatures shift precipitation into heavier, shorter bursts with longer dry spells, which is worse for rivers than steady rain. Mountain-fed systems like the Rhine and Po rely on glacier melt and snowpack, which are declining. He concludes that the historical baseline for climate is gone.
In Central Europe, Hunger Stones carved with inscriptions like 'If you see me, weep' were left as drought warnings, and Godfrey notes that climate scientists have warned for decades, but little action was taken. His article reflects a personal and urgent tone, contrasting with the more measured reporting from Travel Tomorrow, but both sources converge on the role of climate change in the current situation.