The previously unknown ancient metropolis was unearthed in the course of the implementation of an urban transformation project initiated by Turkey’s Housing Development Administration’s (TOKİ) in Nevşehir province of Central Anatolia.
While carrying out earthmoving works in the area, which was meant to be used for the construction of new buildings, the developers stumbled upon a massive underground network of cave tunnels, escape galleries and chambers spanning over 3.5 miles (7 kilometers).
Read more: http://themindunleashed.org/2015/03/huge-5000-year-old-underground-city-discovered-in-turkey.html