A plaque and memorabilia collection mark where A&W got its start.

An artsy hidden staircase leads to breathtaking views of San Francisco.

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

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

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

This artificial cave looks like something out of a fairytale.

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

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

Walk through Czech history in Prague's largest graveyard.

Macabre astrological automaton clock dating to the late 1400s.

The hidden lair of an alchemist rediscovered in a 2002 flood.

A Jenga-style cylindrical tower of books that appears to go on forever.

Fantastic views and thousands of love locks.

Carved fountains poignantly placed in parks and in front of special monuments.

The entrance to this Frankfurt subway station looks like an old tram car crashed into the concrete sidewalk.

Belgium’s famous peeing statue has worn many hats (and coats, and pants), which are on display at this small museum.

Brussels' favorite peeing boy has a sister.

A little sculpture with a large wardrobe.

Meet the bronze beloved pet to a family of famous peeing statues.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Climb inside an iron crystal magnified 165 billion times its normal size.

A dilapidated space station with overtones of 'Alien' and 'Bladerunner' featuring a multiplayer games galore.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.