A total of 22 tiny bridges cross this canal of the Yvette River, forming a unique trail.

At Monet's beloved home you can still see the Japanese bridge, waterlilies, and weeping willows that were the subjects of some of his most iconic paintings.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

Architect Le Corbusier built his friend a cubist house to match his impressive collection of cubist art.

Former hunting lodge of a duke who was an avid collector of impressionist works.

The headless bodies of more than 1,300 guillotined victims of the Reign of Terror are buried here in mass graves.

An immersive projection art installation uses sound, scale, and light to take visitors inside classic works of art.

A modern-day Lascaux cave underneath Paris.

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

Noirish green neon marks the location of one of the oldest private detective agencies in France.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

An off-the-beaten-path boutique stuffed with an eclectic collection of upcycled goods.

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

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

This off-limits room in the National Library of France is home to a system of pneumatic tubes, once used to bring books to readers.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

150 or so scrounged-up lamps, chandeliers, and lanterns light up this alley in central Athens.

This sixth-century church housed an icon with eyes so beautiful legend has it they inspired the name of a Greek city.

This small museum once served as a royal hunting pavilion for King Otto Friedrich Ludwig.

This small chapel holds the mummified heart of one of the heroes of the Greek Revolution.

This beehive tomb built for royalty sat hidden for over 3,000 years.

A crushed gate and giant bronze head serve as a reminder of Greece's fight for freedom.