Beneath the bustling streets of the stunning Italian city of Naples lies a hidden warren of ancient passageways that stretch for more than 280 miles.
The epic scale of underground architecture can trace its origins back more than 2,500 years starting with the Ancient Greeks, followed by the Romans and then expanded by various rulers up until the 1800s.
A cavernous section built by King Ferdinand II of Bourbon in the 19th century was used later by 200,000 locals during the Second World War as an air raid shelter to escape devasting bombing above.
Later some of the caves began to be used as a dumping ground for old cars and rusting vehicles from the 1940s and 50s still line some of the fascinating subterranean corridors.
Now open partially open to the public, underground Naples offers a unique insight into layers of history built up over millenia with Roman statues sharing the same space as wartime gas masks.
The nearby volcano Mount Versuvius holds the key to why so much of the ground underneath Naples has been excavated over the years.
The strong volcanic bedrock under the city has been mined for centuries and provided the perfect material for the Greeks, Romans and later civilisations to construct their most impressive buildings.
According to Underground Naples, during Roman times a vast network of subterranean aqueducts was built “fed by underground conduits coming from the sources of the Serino, 70km (40 miles) away from the centre of Naples”.
Historian Professor Micheal Scott told the Guardian it was the Romans who really expanded on what had gone before. Speaking about filming for a documentary for the BBC, he told the paper: “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.”
For the programme Italy’s Invisible Cities, Prof Scott said he and a team worked at 3D mapping large parts of the tunnel network to hand to local archaeologists.
