Archaeologists have made a surprising discovery in Greece, revealing that wine was not, as previously thought to be, the only alcoholic beverage of choice in ancient Greece.

A new study published in the online journal Vegetation History and Archaeobotany has uncovered two sites suspected to be breweries dating back to the Bronze Age, which could be the oldest beer-making facilities in Greece.

Funded in part by the European Research Council project PlantCult, archaeologists discovered the remains of several buildings at Archondiko in northern Greece, and another at Agrissa towards the east. Impacted by fire, as a result they have been turned into time capsules with a number of insightful artefacts left behind.

One of the clear indicators pointing to the sites being used for beer production were the 100 individual sprouted cereal grains found at Archondiko, which date back to around 2,100 to 2,000 BCE, and the additional 3,500 of them at Agrissa from 2,100 to 1,700 BCE.

“I’m 95 per cent sure that they were making some form of beer,” Associate Professor of Archaeology at Aristotle University of Thessaloniki and study researcher Tania Valamoti told Live Science.

“Not the beer we know today, but some form of beer.”

Archaeologists also found a two-chamber structure at Archondiko that was seemingly constructed to maintain low temperatures, along with special cups at both sites suspected to have been the vessels in which they served the beer.

“It is an unexpected find for Greece, because until now all evidence pointed to wine,” said Valamoti.

Aside from uncovering that wine was not the only alcoholic beverage of choice, the findings also indicated to researchers that the Greeks consumed alcohol all year-round, and not just on a seasonal basis as was formerly believed.

However Valamoti revealed in the study that textural evidence from historic periods in Greece clearly shows that beer was considered an alcoholic drink of foreign people, and barley wine a drink consumed by the Egyptians, Thracians, Phrygians, and Armenians.

While the discovery is the oldest known evidence of beer in Greece, it is not the oldest in the world, with Egyptian records indicating that people consumed beer as early as the mid-fourth millennium BCE.