Different point of view.
Napoli Sotterranea (Naples Underground) offers a chance to explore this Italian city from a different point of view. Down a long case descending some 120 feet (40 meters) below the earth, aqueducts, sewer tunnels, rainwater cisterns, caverns, catacombs, and pre-Christian hypogea can be found in the tuffaceous cavities, along with roadway and rail tunnels.
Many years later, the underground network was used as an air raid shelter during the Second World War, and you can still see forgotten war relics such as weapons and vehicles in the tunnels. More recently, the first Hypogeum Gardens in the world can be found, an experiment to grow various species of plants far from pollution, but also light, in the dark chambers underneath the city.