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

An oversized, oddly designed pedestrian overpass has drawn comparisons to a commode for pachyderms.

Commemorating a unique medieval profession: men who collected feces.

Final resting place of the humble physicist who discovered X-rays, and made the invisible visible.

A statue beloved by—and named by—the local townsfolk it represents.

This peculiar museum offers hands-on interaction with seemingly intangible principles of mathematics.

An exact replica of a colossal Olmec head sits atop a pyramid within a Madrid traffic circle.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

A towering monument in Spain has proven to be more labor-intensive than initially planned.

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

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

Commonly acknowledged as the only public monument to the Devil himself.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

The lengthy skeleton of one of the tallest Spaniards of all time is on display in Madrid.

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

An iconic and controversial ancient Iberian funerary urn with a hauntingly penetrating gaze.

This embalmed man is one of the best preserved mummies from the Canary Islands.

This lucky bronze frog was gifted to Madrid by a casino.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

A stone slab in Madrid marks the point from which the distances of Spain's national roads are measured.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

A mysterious ancient elephant said to possess magic powers is now the symbol of a Sicilian city.