Tatlarin Underground City takes place on a hillside called Kale (castle), 10 kilometers away from the Acigol district. It was discovered in 1975 and opened for visitors in 1991. It has been known that the underground city was widely spread, but only a small part of it can be accessed. The size of the city and the numerous churches and supply depots inside suggest that it can be a military base. The unique feature of Tatlarin's underground city is the toilet. L-shaped toilets, which weren’t found in other underground cities in Nevsehir or Cappadocia, exist here.