Cities of the Underworld descends below the streets of major cities such as New York, Cairo, London, and Tokyo to explore the remnants of subterranean civilizations left buried there.
Beneath the hustle and bustle of Paris streets is a world of snaking quarries, hidden catacombs, and mushroom-harvesting tunnels. Even Paris' 10.5 million residents have no idea they live on top of nearly 20 centuries of history.
S1E4 44 min
