Ancient pottery and coins unearthed by the archaeologists helped date the city to at least 2,500 years ago.
"Our oldest finds are from around 500 BC, but the city seems to have flourished mainly from the fourth to the third century BC before it was abandoned for some reason, maybe in connection with the Roman conquest of the area," Rönnlund said.
The researchers hope to avoid traditional excavation and plan to use ground-penetration radar instead. The technology will enable the team to leave the site in the same shape as it was in when they arrived.
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The finding promises to reveal more about the history of this rather overlooked part of Greece.
"Very little is known about ancient cities in the region, and many researchers have previously believed that western Thessaly was somewhat of a backwater during antiquity," Rönnlund said.
"Our project therefore fills an important gap in the knowledge about the area and shows that a lot remains to be discovered in the Greek soil," he added.
A second field project is planned for August next year.
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