An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

Commemorating the 19th-century labor movement in Australia.

One of the oldest theaters in Australia, it's also said to be haunted by a performer who died on stage.

Once housing children next to hardened criminals this historic jail once displayed Ned Kelly's skull until it was stolen.

This historic Melbourne bullet factory is fully encased in a massive glass and steel cone.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

One of the last doorless, continuously moving elevators still in use in the U.K.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

The last bastion of Roman presence north of the Alps looms over a German town.

This natural sea cave hides a small wonderland of natural turquoise beauty.

An unusual, super-sized grocery adventure awaits in an Ohio suburb.

The Trappist monk, prophet-poet, and rebel never really got to live out the eremitic life he was seeking.

This humble star-gazing center touts itself as the "Birthplace of American Astronomy."

This magnificent Cincinnati graveyard is also a popular public park.

Hidden on two floors of downtown building, the library has an incredible deal on rent.

What is it about mushrooms that makes people wish they lived inside of them?

An art deco ice cream shop covered in vintage tiles.

The park is home to the United States's only still-operating Dutch windmill.

A small island abbey is the final resting place of many medieval Scottish monarchs, including the real Macbeth.

Semaphore saints, a golden dragon's head, and a stone carved with religious warnings all call this cathedral home.

Brisbane's manmade urban beach has enough water to fill five Olympic-sized swimming pools.

Started nearly 100 years ago, this science experiment just keeps on going, ever so slowly.

The pillar of this bridge contains a small home and underneath, a ballroom.