The tunnels housed the city's primary water supply system until the late 19th century.
The network includes the remains of a Greco-Roman theater where the Emperor Nero is historically rumored to have performed.
During World War II, the tunnels were retrofitted with electricity and bunks to serve as official bomb shelters for the local population.
Traces of graffiti and wall inscriptions from different historical eras remain preserved on the tuff walls.
The subterranean cavities feature a unique microclimate that allows for the growth of specific vegetation in certain areas.
The tunnels served as a refuge for the city's poor, sometimes called 'pozzari', who lived in the cavities for centuries.
Naples Underground, known as Napoli Sotterranea, is a complex network of subterranean tunnels and cavities located 40 meters below the city's historic center. These spaces were originally excavated by the Greeks for tuff stone to construct the city and later expanded by the Romans for an intricate aqueduct system. The tunnels served as air-raid shelters for thousands of Neapolitans during World War II. The site features an ancient Greco-Roman theater buried beneath later residential construction. Visitors traverse narrow passages that maintain a constant temperature throughout the year. The route includes access to a series of cisterns that supplied the city with water for centuries. The site showcases the integration of historic architecture with the natural geological composition of the region.
The illuminated cistern chamber where water levels are visible against the ancient masonry.
Wear comfortable, non-slip rubber-soled shoes as the stone floors can be slippery and uneven.
Carry a light jacket, as the temperature inside the tunnels is significantly cooler than on the surface regardless of the season.
Expect to walk through very narrow corridors; those with severe claustrophobia should consult with staff before entering.
Avoid booking unofficial tours from street promoters, as the authorized entrance is specifically marked at the registered address.
Maintain silence in narrow passages and follow the guide's instructions regarding touch-sensitive historical surfaces.
