The famous winding walk at Chartres is surrounded in mystery and myth.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

A quaint medieval millhouse hovers surprisingly above the waters of the Seine.

The man who introduced reinforced concrete to the world demonstrated its genius by using it to build his own house.

This massive blockhead sculpture hides an entire library.

A place to see how French aristocrats lived in the early 1900s.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

This 13th century Gothic brick castle is the largest in the world by surface area.

A mysterious emblem tucked in an small alleyway is actually the coat of arms of a heroic medieval family.

A merchant court dedicated to the fictitious King Arthur is heavily adorned with bizarre Renaissance art.

A modern-day Lascaux cave underneath Paris.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

The remaining relics of the patroness of Paris lie in a chapel under a striking double spiral staircase.

The mummified heart of Louis XVII, the lost dauphin of the French Revolution.

The Cimetière des Chiens et Autres Animaux Domestiques is one of the oldest pet cemeteries in the world.

Empty, but not abandoned, this cavernous Brooklyn loading dock was once considered the largest individual building in the world.

A former seaside jewel built for the everyman is now simply a neglected art deco fortress.

This Queens hospital has stood abandoned for almost 20 years after its patients were secretly relocated in the dead of night.

This futuristic airport terminal was abandoned for decades before reopening as a hotel—with a vintage plane of its own parked out back.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This verdant, tree-lined Reykjavik graveyard is both enchanting and eerie.

Southern Italy's spinning top village.