(CNN)Archaeologists have unearthed a well-preserved ancient Roman neighborhood complete with mosaics and furniture on the outskirts of a city in southeastern France.
The team made the find while excavating an almost 7,000-square-meter site on the banks of the Rhone River in Vienne, where three new buildings were planned.
Archaeologists have been working on the site in southeastern France since September.
"This is an incredible discovery because it's the biggest excavation of a Roman site in almost 50 years," Benjamin Clement, the scientific manager of the operation, told CNN.
"We knew that the zone was rich but we were not expecting that," Clement added. "It's so well-preserved."
French authorities have classed the site as an "exceptional discovery".
Parts of the town could date back to the first century. The excellent condition of the remains is particularly surprising because the team believes that two separate fires assailed the town in the second and third centuries AD.
Photos: Discovered: Incredible treasures found in unexpected places
Photos: Discovered: Incredible treasures found in unexpected places
Archaeologists unearthed a well-preserved ancient Roman neighborhood in the suburb of Sainte-Colombe in southeastern France. They were excavating a site where three new buildings were planned.
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Photos: Discovered: Incredible treasures found in unexpected places
Earlier this summer, the charred remains of a lavish third-century home are the most recent discovery found during the construction of Rome's new metro line.
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Photos: Discovered: Incredible treasures found in unexpected places
This discovery is particularly interesting because the fire that destroyed the house left some things intact, including wooden beams that, under normal circumstances, would have decayed ages ago.
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Photos: Discovered: Incredible treasures found in unexpected places
Items from ancient times are found more often than you might think. In September 2015, British archaeologists discovered a small but prehistoric site that they say provides a genuine snapshot of life in the Bronze Age, some 3000 years ago.
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Photos: Discovered: Incredible treasures found in unexpected places
The earliest known stone copy of the Ten Commandments sold at auction in Beverly Hills in 2016 for $850,000.
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Photos: Discovered: Incredible treasures found in unexpected places
The stone was first uncovered in 1913.
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Photos: Discovered: Incredible treasures found in unexpected places
"The tablet's significance is testament to the deep roots and enduring power of the Commandments that still form the basis of three of the world's great religions: Judaism, Christianity and Islam," says David Michaels, director of ancient coins for Heritage Auctions, who will be conducting the sale.
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Specialists at Mossgreen auctions in Australia discovered this Ming dynasty banknote hidden inside the head of this 14th century Buddhist carving. The wooden sculpture represents the head of a Luohan -- an enlightened person who has reached Nirvana in Buddhist culture.
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Its face value was worth roughly $98 at the time of its circulation and the 700-year-old banknote is believed to have been handmade during China's Ming dynasty. Together, the banknote and sculpture are expected to fetch between $30,000 to $45,000 at auction.
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After studying the banknote and carving details, art specialists were able to estimate the sculpture's age, which dates back to China's Hongwu period in the 14th century.
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Photos: Discovered: Incredible treasures found in unexpected places
Mossgreen specialists believe this is the first time a Ming dynasty banknote has been found inside a wooden Buddhist sculpture. They say it's more common to find relics and semi-precious stones left by monks inside Buddhist sculptures.
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Ten ancient Roman and Ottoman coins were recently discovered in castle ruins in Okinawa, Japan. This image shows the front of one of the Roman coins.
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Photos: Discovered: Incredible treasures found in unexpected places
"I couldn't believe they'd found coins from the Roman empire in Kasturen castle," archiologist Hiroyuki Miyagi, from Okinawa International University, told CNN. This is the front of one of the Ottoman coins.
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Archaeologists recently unearthed a rare 2,000 year old Roman coin during a scientific dig in Jerusalem. The gold coin features the face of Emperor Nero and was likely struck in 56-57 AD.
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Photos: Discovered: Incredible treasures found in unexpected places
In August 2016, the world's largest pearl was discovered under a bed in the Philippines, where it had lain forgotten for over ten years.
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This 1,109 carat, tennis ball-sized diamond made headlines in November 2015 when it was pulled out of the Karowe Mine, in Botswana, by Canadian company Lucara Diamond Corp.
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In May 2016, divers discovered a 1,600-year-old shipwreck while swimming the ancient Roman port of Caesarea. These rare bronze artifacts were recovered from the ship.
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Over 1,300 pounds (590 kg) of bronze Roman coins dating to the 3rd century A.D. were unearthed in April 2016 by construction workers digging a trench in Spain.
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In January 2016, over 4,000 Roman coins were discovered by a fruit and vegetable farmer on a molehill in his cherry orchard in Switzerland.
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The bead on this bracelet, from Portland-based design company William Henry, is actually made using fossilized mammoth tooth and dinosaur bones.
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Preventive excavations began in April, as the team worked to prepare the site for the new buildings.
France has classed the site as an "exceptional discovery," allowing the archaeologists, who were due to finish the excavation in September, to continue until December.
"Our job now is to collect the mosaics, take photographs and archives of the soil," Clément said. "We have two-and-a-half years to keep and restore [the artifacts]. Then, we will have to return them to the state."
The public will have a chance to view the archaeologists' findings, with exhibitions planned for 2019 and 2020 at the museum of Saint-Romain-en-Gal.
