Deep below a Turkish city lies an 18-storey subterranean city that dates back thousands of years but went undiscovered for ...

We're about to head underground into a secret shelter deep in the heart of London! Just like Paris, there's a whole hidden world beneath the streets of the city. We're talking about an abandoned air ...

Nestled within a central Turkish region is a subterranean city, where 20,000 people could live for months at a time. Originally known at Elengubu, the ancient city of Derinkuyu stretches more than ...