The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

Gargantuan home of Russian science.

The tallest hotel in Europe.

World's largest bell sits on the grounds of the Kremlin in Moscow.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

Moscow's other, lesser known kremlin is a fairytale-like cultural complex modeled after Old Russia.

Perhaps the tiniest sculpture in Saint Petersburg is a little bronze finch inspired by a song.

A scale model of Russia so big visitors are offered binoculars to rent so they can see the whole thing.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

This spooky statue sits outside a famous Prague theater.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

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

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

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

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 hidden lair of an alchemist rediscovered in a 2002 flood.

Macabre astrological automaton clock dating to the late 1400s.

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

High on a hill overlooking Los Angeles lives a world famous, high-power conical Tesla Coil.

The legendary building that needed ghostly approval before being built.

This little replica of Lady Liberty provides a bit of NYC in a Japanese city.

No building in the world leans as far as the so-called “Leaning Tower of Abu Dhabi.”