A rocky region in Anatolia - now the Nevshehir province of central Turkey - Cappadocia is an area best known for its sparse and rugged terrain and stunning rock formations. Because of this unique geography, Cappadocia has often existed apart from the Empires that grew and flourished outside its borders. Alexander the Great, for instance, was unable to subdue the region fully during his lengthy military campaigns, and was forced to settle for a nominally autonomous kingdom - led by its own king - existing inside the borders of his own Empire.
Arid and open compared to Constantinople's lush density, Cappadocia is best known to outsiders for its two hundred underground cities and villages, a few of which once housed and sheltered populations of over ten thousand people between the years 600 and 1400 BCE. Literally carved into the soft rock prevalent throughout the region, these cities were fully functioning colonies comprised of hundreds of narrow tunnels and caverns connecting dozens upon dozens of rooms, including living quarters, chapels, granaries, kitchens, wine and oil presses, ventilation shafts, and stables. The largest of these cities, Derinkuyu, was built to a depth of 85 meters and consisted of eleven interlocking levels with more than fifty ventilation shafts.
Beginning in the thirteenth century, when the Byzantine Empire was crumbling and the Emperors could no longer protect their subjects living on the ever-shrinking borders of their kingdom, wayward Christians took to living in the hidden cities for extended periods to stay hidden from encroaching Muslim populations. It is unclear when these cities were eventually abandoned, but it is likely that small populations occupied them in some capacity up until very recently, when the majority of the cities still intact were turned into tourist attractions.