The people here call it underground city, some say it was a Hittite prison. In Byzantine times it had served as a monastery. The origin of this cave system is unknown. Unique (only comparable with the monastry of Eski Gümüsler, 230km further in the south) is that the people had cut a rectangular hole into the rock, about 10m deep. This hole is surrounded by the cave system with windows to the open inner space and cave rooms in the rock. To get into it you have to walk through an underground passage. The walls show a few decoration and it looks as if there had been some wall paintings.