The historian Michael Scott’s worst moment in the miles of tunnels deep under Naples, which he has been exploring for a BBC documentary, came not from fear of earthquake or volcanic eruption, nor among crumbling Roman quarries or the eerie rusting remains of cars seized and dumped under Mussolini’s regime. However, he was extremely unhappy when, in a cramped, airless space heated by volcanic gases, reached by a narrow, 2,000-year-old passage, he met a scorpion.

“It was a small scorpion, but it was a very confined space, and all I thought I could remember about scorpions is that the small ones are more venomous. I stayed very, very still and tried to look unthreatening until it went away.”

Scott, associate professor of classics and ancient history at the University of Warwick, was a conventional above-ground historian, interested in the development of urban spaces, until he crawled down a narrow shaft into a Roman catacomb and was hooked by the underworld.

“The Greeks built tunnels where they needed them but weren’t much interested in going underground – but the Romans went for it big time. We think of cities as being above ground, but they are powered by underground structures, thousands of years of layers of history often unexplored and unmapped,” he said.

“Often they have been explored in parts, but the 3D maps and the raw data we have handed over to the local archaeologists are the first time anyone has tried to fit the jigsaw of these places together.”

Facebook Twitter Pinterest Naples, with the Vesuvius volcano in the background. Photograph: Freddie Claire/BBC

The scores of wrecked vehicles under Naples, including taxis and motor scooters, were seized under Mussolini and then dumped in the tunnels, built a century earlier by a Bourbon king of Naples and Sicily, Ferdinand II.

Ferdinand became increasingly paranoid about conspiracies, though after three revolutions, a 16-month exile and an assassination attempt in 1856, he had good reason to fear his enemies. His tunnels were a massive operation, bridging an underground river and taking in mines dug by the Romans, and were constructed as an escape route between his palace and his main army barracks.

Scott, who explored them with the presenter Alexander Armstrong for Italy’s Invisible Cities, which follows 2015’s Rome’s Invisible City and starts on BBC1 on 4 January, found that although Ferdinand never used them, they saved the lives of thousands of Neapolitans who took shelter there during wartime bombing.



“One of the strangest things I saw there was a bottle of hair lotion, perfectly intact, still with that citrus smell of a gentleman’s hairdressing establishment. Who, in the middle of a war, thought of grabbing it and taking it with them? It may be that the line: ‘My dear, this could be our last night on Earth’ was spoken many times down in the darkness.

Facebook Twitter Pinterest The Church of St Mark, St Mark’s Square, Venice. Photograph: Freddie Claire/BBC

“There are no records of the wrecked vehicles, who they were seized from, why they were just dumped, and what happened to their original owners. Each has a story to tell, but we just can’t read it.”

Scott and Armstrong also explored Florence – climbing into a recently discovered space under the famous Medici tombs carved as a refuge by Michelangelo – and put on scuba equipment to swim among the murky canals of Venice.

“In Venice they said that I would of course have some protection before diving. It turned out they meant medicated olive oil to be sprayed into my ears, because you can’t wear ear plugs with scuba gear, and that was it. So I had lovely gleaming ears, but nothing else. I tried very hard not to swallow.”