Beneath the busy streets of Naples’ historic centre, Naples Underground — Napoli Sotterranea — is a network of tunnels, cisterns and chambers carved into volcanic tuff. Entering near Piazza San Gaetano, visitors descend into a quieter version of the city, where the spaces beneath the streets reveal how Naples was built and sustained.
The Greeks quarried stone here from around the fourth century BC, and the Romans later expanded the subterranean network to carry and store water. The aqueduct served Naples for centuries before falling out of use in the 19th century. During the Second World War, the chambers found a new purpose as air-raid shelters; wartime objects and traces left by those who sheltered here give the ancient site a distinctly human dimension.
A guided tour moves between vast cisterns and narrow passages, connecting the engineering of ancient Naples with the experiences of its residents during the war. The contrast between the cool, still chambers and the clamour of Via dei Tribunali above is part of the appeal. Some tours include an optional, particularly tight passage lit by candles.
Check tour times and languages before visiting, especially on busy weekends. Wear comfortable shoes for the stairs and potentially damp, uneven floors, and bring a light layer for the cool underground air. If you are claustrophobic, ask the guide about skipping the narrow passage before you enter.