This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Walk through spectacular aisles of hanging meat and wagon wheel–sized cheese at the world's largest wholesale food market.

A Belle Epoque bordello turned into a themed love hotel.

The Lone Star plaque hangs in a bombed-out bunker in Normandy to honor a Texan colonel's heroic actions on D-Day.

The heaviest gold coin ever minted.

This French anatomy museum greets guests with a skinless man, mid-shovel.

The approximate spot where the last Grand Master of the Knights Templar was put to death.

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

A daring D-Day assault by U.S. Army Rangers is commemorated atop the high cliffs of this strategic point.

A massive, secret marina for the Nazis' most formidable weapon in the Atlantic.

Underneath a chalk hill in France lies what Hitler hoped would be the underground launching base for a devastating new weapon.

Dedicated to the history and culture of smoking, this small museum now includes a vape lounge.

The construction of a tram line unveiled hidden remnants of the old medieval city.

These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

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

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

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The train platform where Jews were sent to concentration camps is now preserved as a Holocaust memorial.

The only museum with its curator—and her pets—buried inside.