This seemingly out-of-place gas station by the Watergate hotel was once described as the most expensive gas station in the world.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

The world's longest known cave system.

Climb inside an iron crystal magnified 165 billion times its normal size.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world’s largest coastal brick fortresses.

A plain wooden seat that once belonged to one of the most prominent figures of the Protestant Reformation.

Montmartre's sole surviving windmill became an iconic landmark for 19th-century painters, artists, and bohemians.

A beautiful Victorian statue shows France's enduring love of the rhinoceros.

Stripes of human ashes cover a back lawn in the most sought-after burial grounds in Paris.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

A museum of carnival attractions where you are invited to ride the rides.

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

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

Maybe the most iconic character in the Easter (Holy Week) processions in Zamora.

Dedicated to one of the author's most iconic works.

Two large posteriors in one giant statue.

An Antoni Gaudí masterpiece in Astorga.

Designed by Gustave Eiffel before his famed tower.

This enchanting green space houses a labyrinth lined with toxic plants.

Guitarist Paco de Lucía overlooks travelers as they pass through this train station dedicated to his legacy.

Hundreds of preserved dinosaur footprints can be found along a hiking trail in this small village.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.