The strange Cappadocian landscape consists of volcanic rocks that were, for many centuries, exposed to erosion by wind and water. The tufa is soft and can easily be worked. Therefore, people started to make artificial caves; cave dwellers in eastern Anatolia are mentioned in the fourth century BCE by the Greek publicist Xenophon.note[Xenophon, Anabasis 4.5.25.]
Later, in the fourth century CE, churches and rock houses were created for monks who lived here according to the Rule of Basil the Great. They became shelters for refugees during the great wars between the Byzantine and the Sasanian Empires. Several caves are still inhabited and shown to tourists.