The tomb was guarded by soldiers from both sides of the war, and some left their initials carved in the brick.

Copenhagen's celebrated theme park and gardens.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

The art museum is decorated with creatively remodeled pre-Nazi swastikas.

The gilded, masterful astronomical clock will calculate time, dates, and planetary positions for thousands of years to come.

Bored potato-guarding Nazis etched their thoughts onto a brick storage building in Copenhagen's Meatpacking District.

The graveyard holding the remains of George Washington's slaves was forgotten for nearly 200 years.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

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

The massive machine creates cracking displays of indoor lightning.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

An eerie collection of the surviving structures from a past celebration of the future.

The narrowest house in America is seven feet of pure spite.

The oldest building in the District of Columbia was preserved because of a mistaken connection to George Washington.

An ivy-covered arch bridge dedicated to Tejano music singer and legend Rosita Fernandez.

According to a satirical conspiracy theory that persists today, this German city of 300,000 is a hoax invented by the CIA.

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

In an area where the remnants of WWI are discovered on a regular basis this preserved frontline trench may be the most amazing.

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

An old-timey peepshow allows visitors to gawk at some of the world's most freakishly large footwear.

Allowing humans and fish alike to migrate from freshwater to saltwater and back again.

This working class sculpture pounds his hammer all the livelong day.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.