Location : Kütahya
The caves are located at 55 km away from Kütahya, in the Inlice quarter of last Kütahya village of Ovacik, where the city borders of Kütahya, Afyon ve Eskisehir intersects.

Properties : There are hundreds of caves inside the Frig valley which covers an extremely wide area and these caves are carved by hands for the purposes of shelter, accommodation and tombs. Inside the first section of rocks, two churches were discovered. There are frescos on the walls of these two churches named Tekli Kilise (Single Church) ve Çiftli Kilise (Double Church), respectively. Also inscriptions written by root paint are present on the walls. Meander patterns and cross signs are also visible. This valley was used by Frigs between years BC 500-600 and later on, by Byzantiums.
The Deliktas Castle, which was examined in two parts, are also used by Frigs and Byzantiums. For shelter and defense purposes the rocks were carved. There is a large chapel founded here. Secret passages and galleries connect lots of rooms and chambers to each other. The upper parts of the rocks are carved in the shape of ramparts. The third section is the place where a natural castle called Penteser castle is present. This place is also carved for defense purposes and there are various tombs and caves present at this location. This valley is covered with pine trees and the natural beauty can challenge the beauty of Ürgüp.