The Theopetra caves 5 kilometres (3.1 mi) south of Meteora had inhabitants fifty millennia ago
The oldest known example of a man-made structure was found within a prehistoric cave in central Greece, according to the Greek culture ministry. The structure is a stone wall that blocked two-thirds of the entrance to the Theopetra cave near Kalambaka on the north edge of the Thessalian plain. It was constructed 23,000 years ago, probably as a barrier to cold winds. “An optical dating test, known as Optically Stimulated Luminescence, was applied on quartz grains nested within the stones. We dated four different samples from the sediment and soil materials, and all provided identical dates,” Nikolaos Zacharias, director of the laboratory of archaeometry at the University of Peloponnese, told Discovery News. According to a statement by the ministry of culture, “the dating matches the coldest period of the most recent ice age, indicating that the cavern’s inhabitants built the stone wall to protect themselves from the cold.” Excavated since 1987, the Theopetra cave is well known to palaeontologists as it was used and inhabited continuously from the Palaeolithic period onwards (50,000 to 5,000 years ago).[5] In the 9th century, an ascetic group of hermit monks moved up to the ancient pinnacles. They were the first people to inhabit Metéora. They lived in hollows and fissures in the rock towers, some of which reach 1800 ft (550m) above the plain. This great height, combined with the sheerness of the cliff walls, kept away all but the most determined visitors. Initially the hermits led a life of solitude, meeting only on Sundays and special days to worship and pray in a chapel built at the foot of a rock known as Dhoupiani. As early as the 11th century AD hermit monks were believed to be living among the caves and cutouts in the rocks. The exact date of the establishment of the monasteries is unknown. By the late 11th and early 12th centuries, a rudimentary monastic state had formed called the Skete of Stagoi and was centered around the still-standing church of Theotokos (mother of God). By the end of the 12th century, an ascetic community had flocked to Metéora.
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