The massive cave church of Cairo's Zabbaleen community is one of the largest Christian churches in the Middle East.

Hundreds of thousands of ancient documents offer a unique glimpse into Jewish life in Cairo.

An endless sea of white conical domes.

It might not be the prettiest pyramid in Egypt, but it may be the muddiest.

The city-sized home palace of one of ancient Egypt's most powerful rulers gives us a rare look into the lives of the epoch's rulers.

An extensive collection of ancient Egyptian artifacts and mummies.

Years of archaeology, just chillin' by the water cooler.

This replica of an 8th century burial ship actually sailed to Norway before returning home to Minnesota.

A more chill but no less fascinating version of the famous ancient archeological site.

The enigmatic and seldom visited ruins of a Mayan city-state.

A hidden treasure of an abandoned city lies deep in the jungles of Campeche, Mexico.

An elaborate Mayan city shrouded in alien conspiracy revealed the tomb of Pacal the Great.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

The fairy tale castle of the "fairy-tale king."

A crumbling hospital from the 1850s on Roosevelt Island.

The sign at the garden gate reads: "These Plants Can Kill."

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

World's largest collection of serial killer artwork and other macabre exhibits.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

An exquisite tunnel of cascading flowers.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

World's first "penitentiary," meant to be humane, drove men insane.