The moon-scaped region of Cappadocia, southeast of Ankara, lies in south central Turkey and is most known for its unusual geological formations known as fairy chimneys. The surrounding comparatively soft volcanic ash was eroded over time, resulting in the enormous, cone-shaped rocks. In the past, people have excavated them to build homes, fortresses (like Uchisar), and even whole underground towns (like Derinkuyu and Kaymakli), which the early Christians utilized as hiding places. The area's entrance is at Kayseri, which is nearby.