Go inside to really appreciate this 500-year-old technological masterpiece.

The only visible reminders of an elaborate engineering project that kept the tower from reaching the tipping point.

Rome’s legendary peephole vista is also a former Crusader stronghold.

The yawning maw of this pagan visage is said to bite off the hands of liars.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

Two stunning 17th-century libraries and a cabinet of curiosities.

Countless grotesque faces stare out from this eerie Prague art wall.

Tucked away in a Prague park, a statue beloved by romantics honors a poet so nice they buried him twice.

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

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

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

What looks like a suicide in progress is actually a statue of Sigmund Freud.

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

The first museum in the world devoted to sexual gadgetry.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

This bar and museum are devoted to the controversial comic book work of Kája Saudek.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

A mocking tribute to the past and modern leadership of Prague.

This artificial cave looks like something out of a fairytale.

Monument to a suicide protesting the Soviet invasion.

This ancient theater was once the home of fierce gladiatorial battles.

Napoleon's childhood home is now open for people to explore the beginnings of France's short general.