The Kızıl Kilise (= Red Church) had been built in the 6th century. It is the best preserved early Byzantine church in Cappadocia which had not been carved into the tuff rocks. It has its modern name from the red stone it is made of. The Kızıl Kilise is very close to the villige Sivrihisar. Sivrihisar is possibly the Byzantine village Arianzos, the birthplace of Gregor of Nazianz. In the 4th century Gregor was one of the most important theologians in the Byzantine empire and after his death probably buried in the area around the church. Later his bones were brought to Konstantinopel, then stolen by the crusaders in 1204 and returned in 2004.