An incredible mosaic-lined monument said to have held the remains of an ancient Roman empress.

This 6th-century church has the largest and best-preserved collection of Byzantine mosaics outside Constantinople.

Filled with goldfish swimming in a shallow pool of sea water, this ancient crypt is more wishing well than burial site.

This crumbling, graffiti-covered mansion sits tantalizingly within reach of the proletariat who frequent a public park.

An abandoned beach resort in Normandy reclaimed by artists.

This is what trains will look like after the zombie apocalypse.

Deep in the limestone cliffs of the Alabaster Coast, a German fortress built during World War II.

A fortified palace in the shape of a ship on the Thiou river.

A unique military outpost carved into a rocky outcrop in the English Channel.

This "social palace" housing complex created a relatively stable and self-contained worker's society... for a time.

A once drab public housing estate is transformed into a colorful gallery of trompe l’oeil murals.

At this unique farm, you can interact with adorable donkeys and view an ancient dolmen.

Take black faced bears with giant clubs, white faced barbers wielding axes, hunters armed with shotguns, and mix in a lot of drinking.

This bunker in northern France was built by Nazi German forces with the intention of launching up to 50 V2 rockets at London each day.

A quarry cum sculpture park where the works of art are chiseled into the very walls.

This former limestone quarry is now a subterranean wonderland of grand stonework.

The castle where the Marquis de Sade lived out his darkest fantasies.

A resort destroyed by a mysterious bombing offers visitors only its remains and the riddle behind it's demise.

Europe's largest community of crocodiles and alligators.

A unique museum tells the story of the day-to-day life of World War I soldiers.

This secret cemetery where no flag is allowed to fly holds the bodies of American soldiers convicted of heinous crimes during WWII.

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

An abandoned nightclub has become a vibrant work of art.

This French chateau is home to the world’s largest private collection of fighter jets.