A man from Turkey who was looking for his lost chickens accidentally found an ancient underground city that had been forgotten for many years. The man was looking for the chickens when he found out that they had escaped through a hole in the wall of the house. He decided to take down the wall and to his astonishment he discovered behind it a tunnel that leads to an entire city hidden underground.
The case, which happened decades ago, revealed the city of Derinkuyu – which is today considered the largest underground city in the world. The city is at a depth of about 85 meters underground, where it includes eight different levels that are divided into small apartments. According to estimates, about 20,000 people lived in the city in the past who are thought to have preferred to live underground in order to protect themselves from wars or religious persecution.

Over the years, the hidden city has become a UNESCO heritage site, and is part of other underground cities found in Turkey. A few months ago, part of the city was destroyed in the earthquake that struck Turkey along with other similar places.
In recent years, a joint study by an Israeli and Turkish delegation that examined the similarity between the underground city there and the hiding systems built in the Bar Kochba rebellion. It is not clear whether there is a direct connection between the cities, although Talmudic-era accounts state that Rabbi Akiva, the spiritual leader of the rebellion, visited Capotkia (which is identified with the local city of Cappadocia), which may explain the similarity between the places.