A marvel of Byzantine engineering under the streets of Istanbul.

A geological oddity topped with a 2,000-year-old pagan temple.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

A museum glorifying the life of Stalin, located in the city of his birth.

Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

Underground monastery and fortress.

Ancient rock-hewn town that witnessed key events of Georgian history.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

Unusual building appears to be haphazardly built from randomly piled bricks.

Luxury hotel turned into a refugee camp, then turned back into a luxury hotel.

It houses the remains of a 17th-century version of the Titanic.

Go surfing on this urban wave, "hacked" by local surfers.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

One part local history, 99 parts gruesome haunted house.

Famously misunderstood wonder of the ancient world

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

New Orleans' famous cemetery, located on the site of a former race track.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

A snapshot of the city's fascinating voodoo culture.

The oldest cemetery in New Orleans, resting peacefully for over 200 years now.

The final resting place of New Orleans' most famous voodoo priestess.

A 200-year-old bar in the historic French Quarter refuses to give up its place in history, nor its role in securing ours.

Paths are maintained, but trees have taken over plots.