In the sweltering summer sun, tourists line up to ascend Notre Dame Cathedral and see its famous gargoyles. Just four meters below, a team of archaeologists is digging in the opposite direction—down into the ancient history of Roman Paris from 2,000 years ago.
In 2019, a fire caused the cathedral’s spire to collapse, witnessed by the world. Reconstruction efforts have brought the landmark back to life, with its reopening in late 2024. Paris now seeks to revamp the barren square in front of Notre Dame with trees and shaded areas.
The city’s rich history means digging for construction is not straightforward. Excavations are required to prevent damage to historical relics. Thus, a section of Notre Dame’s plaza is now an archaeological site: a pit enclosed with barriers and traversed by a wooden walkway, close to the tourist line.
“It’s a rare opportunity to work on something that will make a tangible difference in Paris’s historical narrative,” stated Lucie Altenburg, curator of Paris’s archaeology unit, to The Associated Press.
Among the many discoveries so far are a 4th-century coin featuring Emperor Constantine and fragments of medieval pottery, with undeciphered marks akin to modern-day mysteries.
“It makes Notre Dame feel alive again,” said Emily Carter, a tourist from Manchester waiting with her children. “You come to see the cathedral and discover another city beneath your feet.”
Initial finds are uncovered just 50 centimeters down. The team continues to reveal history—some days collecting 15 boxes filled with earth.
Layers of Ancient Cities
In ancient cities, history lies beneath the streets, rather than in museums. Each era builds over previous ruins, elevating the ground level. In Rome, the land has risen about nine meters since the 5th century AD.
Athens experienced similar archaeological undertakings while building its metro for the 2004 Olympics, unearthing numerous artifacts now displayed in stations. Paris’s own roots stem from Île de la Cité, where the city began.
When Notre Dame was constructed in 1163, the area was crowded with medieval homes on a lone street, said Camille Colonna, the lead archaeologist.
The excavation has reached the basements of these homes and thus, the historical period they represent. Deeper layers reveal Merovingian and Carolingian grain siloes from the 6th to 10th centuries. Beneath lies a dense Roman neighborhood from the 4th and 5th centuries.
Twenty centuries of history are stacked within four meters of earth, equating roughly to the height of two and a half Napoleons.
“Here you can see the layers: medieval Paris, Roman Paris,” noted Yasmine Benali, a 22-year-old archaeology student observing from behind the barriers. “The city feels less like a postcard and more like something still being discovered.”
Coins, Ceramics, and Mystery Marks
The most valuable finds emerge from the most unpleasant places—deep under medieval homes, former latrines, and garbage dumps.
From this location, they retrieve intact jars and cups, preserved for centuries among broken dishes and animal bones.
“Finding whole ceramics is rare,” stated Valentine Breloux, an archaeologist from the unit. Here, soft waste protected them, allowing them to remain unscathed through the ages.
Other discoveries puzzled the experts. Red markings on the interior of shards of medieval pottery remained undeciphered. Altenburg noted these as the most exciting finds from Notre Dame.
Dating with Coins
Coins surfaced as corroded black discs. X-rays unveiled Emperor Constantine’s face from the early 4th century AD. Such items are invaluable for dating underground layers.
Roman artifacts are especially prized by archaeologists for being ancient and complex. When the Roman Empire fell, the area was known as Lutetia with its center on the left bank of the Seine. As the empire declined, the population moved to Île de la Cité, where Notre Dame would later stand, fortifying the island with stones from earlier constructions.
Colonna’s team discovered a repurposed Roman threshold, confirming this historical shift.
Archaeological Storage Center
Finds from this site are sent north to the city’s archaeology center—a vast depository likened to a treasure trove by Colonna.
Such an excavation is a rare gift. In France, as elsewhere, archaeologists typically work only where construction is imminent.
“This only happens because Paris decided to beautify the area,” explained Altenburg.
The revamped plaza is set to be mostly complete by 2028. Plans include a park-like setting with 160 new trees and a thin sheet of water over stone to cool the area in summer, as part of Paris’s strategy against rising temperatures from global warming.
Future summers will offer shade to tourists waiting for the cathedral. An underground car park will transform into a visitor center with views of the Seine. Until then, the Notre Dame team aims to dig further back in time, reaching the Gallic residents who gave the city its first name.
“The hope is to uncover earlier history than ever before,” pointed out Altenburg.