Once a month here on the Molten Sulfur Blog, I run content taken from our book Archive: Historical People, Places, and Events for RPGs. This post is one of eighty entries in Archive, each more gameable than the last!
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Derinkuyu Underground City
Subterranean House
In 1963, a man in Turkey knocked down a wall of his home and discovered a mysterious room behind it. He continued digging and found an intricate tunnel system with cave-like rooms. What he had uncovered was the beginning of an elaborate subterranean network, including discrete entrances, ventilation shafts, wells, and connecting passageways belonging to an ancient city now called Derinkuyu. This was one of dozens of underground cities carved from rock thousands of years ago in the Cappadocia region of Turkey. Though Derinkuyu is neither the largest nor most ancient of the underground cities, it is the deepest and one of the most recently discovered.
Cappadocia is riddled with spires, stone minarets, lava domes, and rough pyramids left over from layers of volcanic ash and erosion of sedimentary rock. Thousands of years ago, the Hittites of Cappadocia discovered that volcanic ash deposits consist of a softer rock, and they began carving rooms from the material. It started out as just storage and underground food lockers. Subterranean rooms maintained a constant temperature, and protected their contents from weather. Eventually, underground tunneling protected the Hittites from attack. The exact dates of the first tunnels are unknown, but estimates place their construction between the 15th century and 12th century B.C. Another theory claims that Phrygians first built the tunnels between the 8th and 7th centuries B.C., while Hittite artifacts were remnants of wars.
There is no consensus for who is responsible for building Derinkuyu, but many groups have occupied the underground city over the centuries. It is believed the city was expanded during the Byzantine era, when early Christians used the tunnels to escape raids by Muslim dynasties. During peacetime, though, the need for underground shelter would fade, and the tunnels served as cold storage and underground barns.
Derinkuyu stretches as deep as 280 feet, but only about 10% of it is currently open to the public, due to possible collapses. Excavation is incomplete, but some archaeologists estimate Derinkuyu could have up to eighteen subterranean levels. Derinkuyu contains churches, food stores, livestock stalls, wine cellars, schools, and temporary graveyards. The caves are large enough to shelter tens of thousands of people. It’s cooler in the underground, and silent. The tunnels would have been illuminated by torchlight, the stone walls stained by centuries of soot. Pillars emerge smoothly from the floors and just as smoothly meld into the ceilings of the tunnels. Most of the homes are formed out of dusty, natural rock, though there are some areas where bricks are piled up as supports. Some of these bricks look ancient, while others are modern.
There are over one hundred unique entrances to Derinkuyu, hidden behind bushes, walls, and under courtyards. Large, circular stone doors weighing up to half a ton can be rolled into place to seal the tunnel mouths. Should invaders breach the city, the tunnels were strategically carved narrow to force invaders to move single-file. And should the city fall, there is an escape route: at least one three-mile tunnel connected Derinkuyu to the nearby underground city of Kaymakli.
Derinkuyu in Play
At the table, the Derinkuyu underground city could be a terrific place for the party to stumble upon accidentally, whether it be abandoned, inhabited, or infested with monsters. An otherwise-abandoned Derinkuyu would make appropriate shelter for thieves’ guilds and the like. PCs from a war-torn region may have grown up in a city modeled on Derinkuyu. Or your party could venture into a town that seems mostly inhabited by the wealthy. After discovering one of the secret entrances in a courtyard or under a bush, your PCs could discover that the poor have been herded into an underground city because the nobles don’t want to see them.