Built to power trains, the engines in this building provided the entire city of Madrid with electricity during the Spanish Civil War.

Strange masks and obscure costumes are housed in this old Madrid corrala.

This small and often-overlooked museum holds some of Spain's finest artistic treasures.

Earth's rocky history has rarely glittered so brightly as it does in this Spanish museum.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.

The earliest known map to show America, discovered by accident at a Paris bookshop.

The morbid items in this small and hidden museum are not for the weak stomached.

This amazing abuela became a diehard metal fan late in life and an icon of Madrid's '80s rock scene.

A lush indoor jungle fills this bustling Madrid transportation hub.

An ancient Egyptian temple in the middle of Madrid, Spain.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

An underground nightclub helped spark a "Singing Revolution."

A 100-plus-year-old mill transformed into a hotel and restaurant.

One of the oldest wine cellars in Germany is now a restaurant beneath Bremen's town hall.

This amazing oasis of art and plants is hidden on the outskirts of Marrakesh.

This vast masterpiece of Moroccan architecture spreads across 20 acres.

Deliberately hidden for centuries, the magnificent Saadian Tombs were eventually uncovered in 1917.

A Moroccan getaway in the mountain range that plays the Himalayas' stunt double.

This dockworkers' lunch joint has been left leaning by a century of storm floods.

This contentious squat has stood through fire, violence, and government intervention as a hotbed of leftist protest.

A fascinating little museum dedicated to the thousands of chemical substances concealed in our food.

Model Trains and Much More in Hamburg.

A wunderkammer of exoticism immortalized by Tom Waits.