(CN) — Archaeologists announced Monday they have produced the first high-resolution mapping of an entire Roman city in Italy buried miles beneath the surface without ever breaking ground.
Using a state of the art ground penetrating radar, researchers were able to map the entire city of Falerii Novi in exceptional detail without disturbing its remains – a technique that could alter scientists’ understanding of these ancient settlements.
In their study published in the journal Antiquity, the team took advantage of the recent advances in GPR technology. This tech has been around since 1910, but in recent years it has been improved to be faster and more accurate, allowing high resolution mapping of large areas that may be out-of-reach.
It works by reading the reflections of radio waves off of far away items underground, accounting for differences of material, and has made way for major breakthroughs in excavations. Archeologists can now study ancient structures even if they cannot be uncovered due to complications.
Using this technology, scientists from the University of Cambridge and Ghent University were able to find a bath complex, market, temple, grand public monument and even the city’s extensive network of water pipes. The GPR has also allowed them to see the city’s development over time by looking at the different depths.
GPR technology builds images of things by sending out radio waves to bounce off of objects and pieces together the picture by reading the echoes. In this endeavor, the scientists towed the GPR instruments behind a quad bike as they drove over the grounds, taking readings every 12.5 centimeters, and allowing for a full survey of the area.
Falerii Novi, located just 30 miles from Rome, was occupied until around 700 AD and was about half the size of Pompeii. Scientists have studied this settlement for decades with various non-invasive techniques, like magnetometry, but GPR has provided the most complete picture. The city has extensive documentation in historical records, but the GPR data shows that contrary to popular belief, it is not covered in traditional modern buildings.
The results of the survey revealed physical details of the city’s structure in unprecedented detail, including evidence of stone robbing and elaborate architecture. In fact, places in the city like the temple, market building and bath complex were more complex and embellished than Pompeii – an impressive feat for a small city.
“The astonishing level of detail which we have achieved at Falerii Novi, and the surprising features that GPR has revealed, suggest that this type of survey could transform the way archaeologists investigate urban sites, as total entities,” said co-author Martin Millett, professor from the University of Cambridge’s Faculty of Classics.
One fascinating find from the GPR data was within the southern district of the city, where a large rectangular building stood connected to a system of water pipes that lead to the aqueduct. These pipes were spread all throughout the city, but instead of running just along the streets, they were also built beneath the settlement’s city blocks, or insulae.
This led the team to believe that this building must have functioned as some form of an open-air natatio or pool, likely part of a public bath house.
An even more surprising find was a pair of large structures near the city’s north gate, which stood facing each other inside a porticus duplex, or an extended colonnade. The authors believe that these pieces were part of a sacred public monument, contributing to the ornate and elaborate architecture of the city.
Millett and his colleagues have used this technique of GPR mapping in the past in similar studies, surveying the Roman colony Interamna Lirenas in Italy, as well as the town of Alborough in North Yorkshire in Great Britain. Moving forward, they hope to repeat this success on much bigger sites around the world.
“It is exciting and now realistic to imagine GPR being used to survey a major city such as Miletus in Turkey, Nicopolis in Greece or Cyrene in Libya,” Millett said. “We still have so much to learn about Roman urban life and this technology should open up unprecedented opportunities for decades to come.”
One set back the team expects to encounter is due to the fact that the GPR data created such detailed results, and therefore a significantly increased workload for anyone analyzing the images. In fact, one person manually analyzing the data could take up to 20 hours, but the authors hope to speed up this process by developing automated techniques to finish mapping Falerii Novi.