This abandoned Navy base was transformed into an off-grid alternative living community for thousands of people.

Disney's abandoned animal island is now an overgrown ruin that was almost the coolest attraction ever.

An astounding annual light display honors the victims of one of Japan's most devastating earthquakes.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

Perched atop the highest hill in Cartagena, this 17th-century convent offers spectacular views of the city.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

Abandoned railway line circling the city of Paris.

A submerged archeological park still holds the wonders of a Roman Sodom.

Stroll through retro Paris while shopping for old postcards and discarded doll heads.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

Village situated on a narrow volcanic escarpment.

A Hawaiian stairway to heaven—that you can't climb.

A swing to dangle you off the very edge.

The world's highest and most dangerous infinity pool lies at the precipice of Victoria Falls.

The fairy tale castle of the "fairy-tale king."

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

A spectacular cave and a beguiling lake.

The ruins of an abandoned medieval city where the last Byzantine emperor was crowned.