A man knocked down a wall of his home. Behind it, he discovered a mysterious room, and an intricate tunnel system leading to an ancient underground city in Turkey, called Derinkuyu.
Millions of years ago the Cappadocia region of Anatolia was buried in ash. Today you can see the lava domes and rough pyramids that were created as a result.
And in 1963 a man in the Nevşehir Province of Turkey knocked down a wall of his home. Behind it, he discovered a mysterious room. After much digging he soon discovered an intricate tunnel system with additional cave-like rooms. What he had discovered was the ancient Derinkuyu underground city.
“The elaborate subterranean network included discrete entrances, ventilation shafts, wells, and connecting passageways. It was one of dozens of underground cities carved from the rock in Cappadocia thousands of years ago. Hidden for centuries, Derinkuyu‘s underground city is the deepest.”
“Derinkuyu is the deepest of the discovered underground cities with eight floors – reaching depths of 280 feet (85m) – currently open to the public. Excavation is incomplete but archaeologists estimate Derinkuyu could contain up to 18 subterranean levels.
Miles of tunnels are blackened from centuries of burning torches. They were strategically carved narrow to force would-be invaders to crawl single-file.
Eventually the tunnels reach hundreds of caves large enough to shelter tens of thousands of people.
The build-out of Derinkuyu accommodated for churches, food stores, livestock stalls, wine cellars, and schools. Temporary graveyards were constructed to hold the dead; an ironic twist, bodies were stored underground until it was safe to return them the surface.
Over one hundred unique entrances to Derinkuyu are hidden behind bushes, walls, and courtyards of surface dwellings. Access points were blocked by large circular stone doors, up to 5 feet (1.5m) in diameter and weighing up to 1,100 lbs (500 kilos).
The stone doors (pictured below) protected the underground city from surface threats, and were installed so each level could be sealed individually. The tunneling architects included thousands of ventilation shafts varying in size up to 100 feet deep (30m).
An underground river filled wells while a rudimentary irrigation system transported drinking water.”
Today Derinkuyu was opened to visitors in 1969, but only about 10% of the underground city is accessible to tourists today.
The underground city is open to visitors daily during the summer from 8 a.m. until 7 p.m. Winter hours are from 8 a.m. until 5 p.m. 2014 entrance fees are 15 Turkish Lira (or about /£4/€5).
A guided tour is more expensive, but recommended, as there is little information within the city itself to indicate what one is observing. Independent local guides will sometimes loiter near the entrance waiting to be hired. The Green Tour (or South Cappadocia Tour) is a highly-rated and popular option. Alternatively, private 2-hour tours are also available.[SOURCE](http://sometimes-interesting.com/2014/05/09/derinkuyu-the-underground-cities-of-cappadocia/)