Tucked away amidst some of the most famous addresses in the world is New York's only fraction of a street.

This ruined fort hidden at the top of Central Park can't seem to keep from losing its historical plaques.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

One of only two commuter aerial tramways in the United States.

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

New York City's smallest piece of private property.

Elevated freight railway turned wildly successful urban park.

Try not to get slimed in Tribeca.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

The mummified relics of an American missionary.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

The largest fountain in Bratislava.

Former headquarters of the KGB.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

An electrical pylon under whose legs a normal gauge train can run.

From Nazi chemicals to the CIA, this architectural marvel has played a fascinating role in German history.

Fantastic views and thousands of love locks.

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

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Cold war icon and onetime "hole" in the iron curtain.

Berlin's old airport.

Golden cobblestones remember a time when this small alley was used to avoid having to give a Nazi salute.

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.