France's most famous cemetery, with some of its most curious tombs.

The largest madrasa in Morocco once housed more than 900 students within its exquisite walls.

It took 40 years to build this Eden-like garden in Marrakech, later restored by Yves Saint-Laurent.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

Home to a protest movement, a bombing, and a dramatic change in labor history.

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

One of the largest wooden constructions in Europe was meant to be a casino, but soon became an orphanage.

Taking the subway here means doing so over a bridge located in the middle of an estuary.

Balanced on four stone pillars, this historic tower was the site of a tragic political assassination.

Quite possibly the oldest love poem known to humankind.

A section of the long chain that blocked enemy ships from entering Constantinople.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Mediterranean castle on a tiny Turkish island.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

The ancient latrines of the Greeks, in all their public glory.

Seven early Christians were sealed into a cave where legend has it they slept unharmed for centuries.

Over the centuries, this island paradise has done it all, from providing monks with ecclesiastical respite to sheltering an exiled Leon Trotsky.

Ancient serpentine sacrifice holder that has stood the test of time.

The ancient abodes are a testament to human ingenuity amid harsh climates.