Get ready to discover a city beneath the city, a hidden world just 136 steps below the bustling streets of Naples. You'll journey through time in this incredible network of tunnels, starting from the ancient Greek quarries that supplied the stone for Neapolis. Imagine these vast caverns first as Roman aqueducts, then as air-raid shelters during WWII, with stories etched into the very walls. The main paths are spacious, but for a little thrill, you can opt for a candle-lit squeeze through a narrow, ancient cistern passage. It's a truly fascinating way to understand the layers of our city's long and complex history.