The video game-themed street art first popped up in the French city.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This demon atop the Notre-Dame de Paris looks utterly bored.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

The site where two doves fell in love.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

The site of the climactic scene from the classic horror film is now a historic landmark.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

The "lovely red Vega" of the legendary record-settling pilot.

Decades before the scandal, this staircase on the river was a literal "water gate."

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Go take a picture with the inventor of the daguerreotype photographic process.

There's a piece of New York City transportation history hidden in plain sight at a Manhattan subway stop.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

The longest continuous underwater road in North America was built at the insistence of Franklin Roosevelt.

Elevated freight railway turned wildly successful urban park.

A popular European tradition makes its way to the states on one of America's most famous bridges.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

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

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

A triumphant marble and bronze fountain depicting a 15th-century Hungarian king and his hunting party.

The geographical center of Budapest is marked with a 10-foot-tall stylized zero.