Archaeologists have unearthed one of the oldest strip malls in the world at the ancient city of Argilos in northern Greece.

The structure is called a stoa in Greek, and is a 40-meter long covered walkway that contained shops. It dates to 6th century B.C.

Porticos were common in Greek cities of the Hellenistic period, a time bookended by the death of Alexander the Great in 323 BC and the emergence of the Roman Empire in 31 BC. The centuries in between saw Greek influence extending through Europe, Africa and Asia, and Greek cities containing these stoas cropped up from Syria to Turkey, Italy and the Mediterranean.

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The stoas functioned as gathering places and as such are foundational in key schools of thought of the Hellenistic period such as stoicism.

The origins of the Greek stoas have been somewhat of a puzzle, which makes the Argilos find important, said Jacques Perreault, a professor at the University of Montreal who excavated the portico this summer with his colleague Zisis Bonias, an archaeologist with the Hellenic Ministry of Culture and Sports.

The city of Argilos predates the Hellenistic period and reaches back to a time before Alexander the Great, and even his father, Phillip II of Macedon. This region of the Mediterranean had then been inhabited by the Thracians, tribes of central and southeastern Europe about whom little is known. The Greeks established Argilos in the middle of the 7th century B.C.

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The region was a frontier where people headed to strike it rich in the valley of Strymon River, where gold and silver overflowed in mines. An “El Dorado,” Perreault calls it. Argilos was the nearest port and transportation hub and it grew to be prosperous.

The portico was built 2,700 years ago, Perreault said. It contains seven rooms of uniform size — 5 meters wide, 7.5 meters deep and 2.5 meters high. The rooms are not identical. They were built using different stones and techniques, which suggests that the shop owners had each hired separate masons for the task.

Argilos flourished till 437 BC, when the nearby city of Amphipolis began thriving. Amphipolis was located closer to the Strymon River and began controlling much of the trade. Over the next century, the Thracians, the Spartans, the Athenians and the Macedonians jostled for control of the city.

In 357 B.C., Phillip II of Macedon (the father of Alexander the Great) conquered Amphipolis, and ordered the residents of Argilos to move to Amphipolis to change the demographics in favor of Macedonians. That was the death knell for Argilos.

The ancient city on a hilltop remained undisturbed until 1992 when Perreault and his colleagues began excavating.

It’s a good thing the city was abandoned, Perreault opines, because later Greeks favored large monuments with deep foundations that would have destroyed the earliest constructions of Argilos.

Greece is one of those nations where the landscape is so littered with ancient history that it becomes difficult to launch public works projects without disturbing some element of the past.

For instance, a stretch of road built by the ancient Romans was found in Thessaloniki, which is about 70 kilometers from Argilos, when workers were digging a subway tunnel. The Culture Ministry decided to relocate the road to be displayed elsewhere, but archaeologists are protesting disturbing the site, according to a report by the Associated Press.

The Attiko Metro, which is building the subway system, has so far spent 75 million euros ($102 million) in excavating archaeological remains, according to the article.

“In countries like Greece, when you plant tomatoes in the backyard, you make a hole and you find something,” said Perreault. “Sometimes you have to make tough decisions.”

Image: An aerial photo reveals the Argilos portico in northern Greece. Credit: Jacques Perreault, Université de Montréal