What Is the Derinkuyu Underground City in Turkey?

Derinkuyu is an 18-level underground city carved into volcanic rock in Turkey’s Cappadocia region, extending 85 meters deep and capable of sheltering 20,000 people. Despite being one of the world’s most impressive ancient engineering feats, archaeologists still don’t know who originally built it.

The Discovery That Changed Everything

In 1963, a Turkish man in the town of Derinkuyu made one of archaeology’s most remarkable accidental discoveries. While renovating his home, he knocked down a wall and found a tunnel leading into a vast underground complex that had been forgotten for centuries. What he uncovered was an entire subterranean city that had been hiding beneath the volcanic landscape of Cappadocia.

Engineering Marvel Carved by Hand

The builders of Derinkuyu chose their location perfectly. The city was carved into tuff, a type of volcanic rock that remains soft enough to cut by hand while underground but hardens like concrete when exposed to air. This unique property allowed ancient engineers to excavate the complex using simple tools while ensuring the structure would remain stable for millennia.

The 18 levels of the city include living quarters, storage rooms, stables, churches, wine cellars, and even a sophisticated ventilation system with over 15,000 air shafts. The deepest levels contained wells that reached down to underground water sources, ensuring the inhabitants could survive extended sieges.

Ingenious Defense Systems

Perhaps the most impressive feature of Derinkuyu is its security system. Massive circular stone doors, some weighing up to 500 kilograms, could only be rolled shut from the inside. These doors blocked narrow passages between levels, making it impossible for invaders to force their way through. The city also featured escape tunnels and could be completely sealed off from the outside world.

A Shelter Across Millennia

Archaeological evidence suggests Derinkuyu served as a refuge for various civilizations spanning over 2,000 years. The earliest inhabitants may date back to 800 BCE, possibly including the Phrygians or other ancient Anatolian peoples. Later, Byzantine Christians used the underground city to hide from Arab raids in the 7th-10th centuries, and medieval Christians sought shelter there from Mongol invasions in the 14th century.

The Enduring Mystery

Despite decades of research, the original builders of Derinkuyu remain unknown. While we know various groups modified and expanded the city over centuries, the identity of whoever first carved those initial tunnels into the volcanic rock continues to elude archaeologists. This mystery adds to the fascination surrounding one of Turkey’s most extraordinary archaeological sites.

Today, Derinkuyu is a UNESCO World Heritage site and represents just one of dozens of underground cities discovered throughout Cappadocia, suggesting that subterranean living was once a widespread practice in this unique geological region.