The largest salt lake in the Sahara is mysteriously alluring.

Think you have a tough job? Try carrying 200 kilos through a cloud of sulfur down the side of a volcano.

Putrefaction plateaus in Iran, where the dead were sent for decontamination before going to their final resting place.

This isolated community does not want you to visit.

A 130-year-old urinal is the oldest of Stockholm and perhaps all of Sweden.

The beautiful baroque library of the Hapsburg empire.

A surreal statue honoring Prague's favorite literary son.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Macabre astrological automaton clock dating to the late 1400s.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

The Pope’s secret escape route.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

2300-year-old Roman road connecting the empire.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Architectureal fantasy quarter of Rome.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

The final resting place of the great navigator, or maybe his brother.