A Turkish homeowner chasing his chickens through a hole in his basement during renovations came across an abandoned underground Turkish city that once housed 20,000 people.
Excavation work uncovered an incredible marvel of engineering, a network of tunnels and shelters 18 levels deep that went down 280ft (85 metres). This enormous underground city is thought to have begun life as a system of caves built back 1200 BC by the Hittites to shelter from the Phrygians, who then in turn further excavated the area and expanded the living space when they conquered the region.
In later centuries it appears as though Christian inhabitants of the Roman Empire expanded the cave systems by adding more layers and including chapels, stables and places to make wine and olive oil.
The underground city of Derinkuyu was a safe haven for the people living in the region on many occasions, with a long string of conquerors and occupiers marching through that part of the world.