Studies suggest that the pinnacles were formed about 60 million years ago during the Tertiary Period. Weathering and earthquakes then shaped them into their present shape.
Beside the Pindos Mountains, at the western region of the Thessaly plain in the middle of northern Greece, these sandstone rocks rise from the ground. The rocks are composed of a mixture of sandstone and conglomerate. They were formed about 60 million years ago. A series of earth movements pushed the seabed upwards, creating a high plateau and causing many fault lines to appear in the thick layer of sandstone.
Continuous weathering by water, wind and extremes of temperature turned them into huge rock pillars, marked by horizontal lines which geologists maintain were made by the waters of a prehistoric sea. Greek historian Herodotus wrote in the 5th century BC that local people believed the plain of Thessaly had once been a sea. If this was accurate, there was most probably an inundation at the end of the last Ice Age, around 8000 BC. However, he failed to mention the rocks of Metéora, and nor are they recorded in the writings of other ancient Greek authors. This has led to the belief that the pinnacles did not exist 2000 years ago; a theory dismissed by modern geologists.
The cave of Theopetra is located at the foot of the cliffs. Excavations and research and have discovered petrified diatoms, which have contributed to understanding the Palaeo-climate and climate changes. Radiocarbon data evidences human presence dating back 50,000 years, The cave is closed to the public.
