Scientists to Map 'Secret' Labyrinth of Roman Subterranean Tunnels
As tourists wonder the streets of Rome and flock to the incredible sites of the Colosseum and Roman Forum, few of them realise that beneath their feet lies something even more ancient – a maze of subterranean tunnels and quarries that date back to the very beginning of this ancient city.
However, the underground network is somewhat of an open secret for the locals because every so often the ancient tunnels collapse, damaging buildings and streets above. Literally hundreds of structures have collapsed in the last three years and the numbers are increasing. So a team of geologists will now be venturing beneath Rome to map these underground passageways with the hope of preventing more buildings from crumbling into the voids below.
"Hundreds of kilometres of catacombs run underneath the town and its outskirts," says Adriano Morabito, president of the association Roma Sotterranea (Underground Rome). "Some of the networks are well known and open to visitors, while others are still scarcely explored. Probably there are a number of lost catacombs, too."
The tunnels first began as quarries as the ancient Romans mined rock to build their city, which later expanded over the tunnels. Then, once the quarrying ended, people began using the underground labyrinth as catacombs, for mushroom farming and as an unofficial sewer system. During World War II, people used the tunnels as bomb shelters.
The team of geoscientists will be using laser 3D scanning techniques to search for hidden weaknesses in the tunnels and to map the whole underground area.
"There might be cracks, so they will be showing as veins almost, or openings, so we map the openings and map any kind of detachment," said geoscientist Giuseppina Kysar Mattietti. In some spots, the ceiling of the tunnel sloughs off like cracking plaster. In others, there are total collapses — sometimes not reaching quite to street level, but leaving very little ground between the surface and the void.
The council plans to fill in weak-spots with cement instead of doing a quick ‘patch job’ as has been done in the past. The difficulties will arise if those weak spots happen to be in areas occupied with the remains of ancient people.
All Christian catacombs in Rome are property of the Catholic Church, and no one is allowed to explore them without special permission from the Vatican. "It's not so easy to get the permission. That's one of the reasons there have been very few archaeological expeditions to less known tunnels in the last decades," Morabito says.
The Christian catacombs are extremely important for the art history of Early Christian art, as they contain the great majority of examples from before about 400 AD, in fresco and sculpture, as well as gold glass medallions. The Jewish catacombs are similarly important for the study of Jewish art at this period