Subterranean

A centuries-old complex of hand-dug stone chambers has sheltered locals in times of trouble.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This vast, water-filled underground labyrinth can only be toured by boat.

This luxury hotel suite is located deep in the bowels of an old mine.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

Wild lights and sound effects turn a walk through some caves into an eye-popping 1960s tourist attraction.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

A 90-year-old underground water reservoir offers a more industrial kind of tranquility.

A monumental underground karstic wonderland is also the water source for over a million citizens of Beirut.

This subterranean disco dance club in a Cuban cave comes with bright lights and a dark legend.

This picturesque Umbrian city has a subterranean side that has long remained hidden.

Michael Jackson got Bad and Crocodile Dundee walked on heads in this iconic Brooklyn subway station.