An underground city beneath a European capital. No one has seen it for 100 years.

Rome has been tempting visitors with countless monuments for years . Now, tourists will have yet another reason to visit the "Eternal City." This is a vast, underground labyrinth located beneath the ancient Roman Forum and the 2,000-year-old Marcello Theatre, which has been off-limits for over a century. The history of these caves (the deepest of which is approximately 300 meters below the surface) dates back to before the time of Julius Caesar. The tunnels will reopen to visitors in 2026 or 2027.

Rome hides an underground city

The first visitors have arrived in the hidden corridors beneath Rome's Capitoline Hill. For now, journalists, in addition to archaeologists, have had access to the mysterious labyrinth. Among others, a CNN crew visited Rome's newest attraction, still off-limits to tourists. "No one has seen these caves and tunnels for over a century," says archaeologist Ersilia D'Ambrosio. The underground chambers are located in the city center, just beneath the Roman Forum and the Marcello Theater, and cover an area of nearly four thousand square meters.

This isn't a completely unknown site – the Grottino del Campidoglio, or Capitoline Grotto, existed here even in the time of Julius Caesar and remained in use until the 1920s. It wasn't forgotten during World War II, when it served as an important bomb shelter. "A walk through the tunnels is a journey through time, revealing the complexity of Roman history. Some of the passages are carefully constructed and brick-lined, testifying to their recent use. Others are merely roughly carved from tuff, the soft volcanic rock from which the famous Seven Hills of Rome were formed," we read.

Opening in a year

The passages are expected to open to tourists in late 2026 or early 2027. Rome's newest attraction will undoubtedly be a treat for history buffs. It will also be a popular destination for those seeking refuge from the scorching summer heat of the Italian Peninsula. While temperatures will reach 30 degrees Celsius on the surface, temperatures underground will drop to as low as 13 degrees Celsius. The price for this experience has not yet been determined.

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