In 1963, a man in the Nevşehir Province of Turkey knocked down a wall of his home, and behind it, he discovered a mysterious room. This room led to a tunnel which led to an incredible discovery: the ancient underground city of Derinkuyu. This underground city is neither the largest nor oldest, but its 18 stories make it the deepest. Extending to a depth of approximately 60 m (200 feet), it is large enough to have sheltered approximately 20,000 people together with their livestock and food stores.
It was most likely used as a giant bunker to protect its inhabitants from either war or natural disaster and could be closed from the inside with large stone doors and each floor could be closed off separately. The elaborate subterranean network included discrete entrances, ventilation shafts, wells, and connecting passageways. It remained hidden for centuries.
Unique to the Derinkuyu complex and located on the second floor is a spacious room with a barrel vaulted ceiling. Between the third and fourth levels is a vertical staircase. This passageway leads to a cruciform church on the lowest (fifth) level. The large 55 m (180 foot) ventilation shaft appears to have been used as a well. The shaft also provided water to both the villagers above and, if the outside world was not accessible, to those in hiding. It had access to fresh flowing water — the wells were not connected with the surface to prevent poisoning by crafty land dwellers. It also has individual quarters, shops, communal rooms, tombs, arsenals, livestock, and escape routes. There’s even a school, complete with a study room.
The city at Derinkuyu was fully formed in the Byzantine era, when it was heavily used as protection from Muslim Arabs during the Arab–Byzantine wars (780-1180). The city was connected with other underground cities through miles of tunnels. Some artifacts discovered in these underground settlements belong to the Middle Byzantine Period, between the 5th and the 10th centuries A.D. These cities continued to be used by the Christian natives as protection from the Mongolian incursions of Timur in the 14th century.
After the region fell to the Ottomans, the cities were used as refuges (Cappadocian Greek: καταφύγια) from the Turkish Muslim rulers. As late as the 20th century the locals, called Cappadocian Greeks, were still using the underground cities to escape periodic waves of Ottoman persecution. R. M. Dawkins, a Cambridge linguist who conducted research on the Cappadocian Greek natives in the area from 1909-1911, recorded that in 1909, “when the news came of the recent massacres at Adana, a great part of the population at Axo took refuge in these underground chambers, and for some nights did not venture to sleep above ground.” When the Christian inhabitants of the region were expelled in 1923 in the Population exchange between Greece and Turkey the tunnels were abandoned.
It was opened to visitors in 1969 and about half of the underground city is currently accessible to tourists, but nothing was heard about the man who discovered it.
Photos found here