There’s a hidden military meme engraved on the World War II Memorial.

The world’s largest underground marble quarry is hiding in Vermont.

Originally built for London’s cab drivers, this bright green hut now serves anyone a hot drink or meal.

The headquarters of one of the world’s longest-running humor magazines bears a noticeable resemblance to a head wearing a Prussian helmet.

This small glass cube is a peaceful out-of-the-way sanctuary at the busy airport.

The Tudor-style cottage in the middle of the square is not quite what it seems.

These lush botanical gardens employ the most purrfect pest control force.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

An unexpected Easter egg lurks in the background of a cherub wall relief at the Breakers mansion.

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.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

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

Two stone columns flank the grand Venice square, but there were supposed to be three.

A relic of FDR's brief foray into utopian urban planning.

The residents at this Yellowstone wildlife park will certify your cooler as "bear-proof."

An obsolete, vanishing traffic device warns Cincinnati drivers away from middle-of-the-road obstructions.

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

One of the last remaining World War II Victory Gardens in the U.S. is quietly growing across from Fenway Park.

The rogue roots are gradually consuming some of the historic marble grave markers.

This small-town Connecticut restaurant gives each diner a free book from its vast library.

Plymouth's huge yet little-known memorial to the Pilgrims.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.