This full-day tour begins in the Devrent Valley, known for its spectacular fairy chimneys and landscapes. Continue visiting Pasabag, or Valley of the Monks, to admire the double and triple-headed rock formations. Goreme Open Air Museum; The Goreme Open-Air Museum is in Cappadocia's heart. The region's most impressive concentration of sights is at the Open-Air Museum, 1km out of Goreme on the Urgup road. The churches here are carved into caves and fairy chimneys. The walls were initially covered in frescoes; you can still see their remnants. The churches are the legacy of Christianity under the Byzantine Empire. In the 4th century, St. Basil founded one of the first Christian monasteries here, setting down religious tenets that influenced the teachings of St. Benedict and, subsequently, the Western monastic movement. The church on the hill before the main entrance to the museum is known as Tokalı Kilise (Church of the Buckle). Inside the museum are five churches: Sandal(Sandal Church), Yilanli (Church of the Serpents), Barbara, Elmali (Church of the Apple, currently closed), and Karanlik. Be sure to visit Sandal and Elmali if they are open. Both contain superb frescoes. The museum is well known for wall paintings that date to the 10th century, depicting the life of Jesus Christ and monks of that time. Avanos; The potters of Avanos have been throwing the red, iron-rich Cappadocian clay since time began. There are roughly a hundred workshops around the area, all with similar prices. Everything here is from high art to American kitsch (there's more of the latter). Avanos itself is a pleasant, European-style town. Its main square contains several lovely cafés. Above the court are whitewashed Greek buildings-it looks like a village on a Greek island. The Kiziılirmak (Red River), Turkey's most enormous, flows through the town. From here, the potters take the red clay for their work. At times, the river is a deep red color. Kaymakli and Derinkuyu Under The Ground Cities: In the villages of Kaymakli and Derinkuyu, inauspicious passages lead to two of Cappadocia's most spectacular sites. Two stark but well-preserved underground cities, considered more than 3000 years old, lurk beneath the ground in an endless warren of tunnels, rooms, stairwells, and hallways. Throughout centuries of political uncertainty, Christians fled from their villages to the underground cities at times of imminent attack. It is estimated that five to ten thousand people lived here for up to six months. Strict, military-style discipline was imposed, and some pillars had holes drilled at the top for chaining transgressors due to torture. It was forbidden for anyone to leave for any reason while the cities were occupied, lest their departure gives away their location. Strangely enough, no toilets have been found in Derinkuyu, though some have been found at Kaymakli. The last stop on tour is Uchisar Castle, one of the region's most massive fairy chimney formations.