This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

A rare example of World War I trenches from the British front.

In the shadow of a former battleground, the resting place for nearly 2,000 soldiers who died in World War I.

This memorial museum chronicles the apocalyptic destruction of the First World War.

A moving memorial to the fallen and missing from WWI trenches.

You can spot this teeny tiny stained-glass window from the Bonifacius bridge.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

A piece of stonework relief commemorates the site where the Devil's rage, and odd apparel, destroyed a house.

This ex-prison dates back to the Middle Ages.

Captain America, Sub-Mariner, and the Human Torch were all born in this art deco Manhattan masterpiece.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Fake subway tiles were installed to cover a design that resembled the Confederate flag—it's unclear if the resemblance was intentional.

Commemorating the spot where the famous scientist fed his pigeons.

The fanciest public restroom in New York City boasts fresh flowers, art, and a classical music soundtrack.

Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

The self-proclaimed gateway to the Extraterrestrial Highway.

The bullet-riddled wall from the St. Valentine's Day Massacre, bloodstains enhanced for your viewing pleasure.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

A statue in the center of Dublin dedicated to one of their favorite sons of rock & roll.

A guitar mounted on a wall in Temple Bar honors the Irish musician.

Experience what life was like in Ireland during the Viking and medieval ages.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.