Did you know?

In 1963, a Turkish man discovered a mysterious room behind a wall in his home. Further digging revealed a network of tunnels that turned out to be part of an ancient multi-level underground city called the Derinkuyu underground city, which extends to a depth of around 279 feet and is large enough to have sheltered around 20,000 people.
Picture Derinkuyu Underground City – An Ancient Multi-level Underground City

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