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

Behind a bodega is a small museum of relics and ephemera showcasing the history of New York.

One of New York's best collections of pinball is hidden in a secret bar in the back of this laundromat.

The "Seinfeld" diner.

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

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

Read a book next to a Midtown waterfall.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A crumbling hospital from the 1850s on Roosevelt Island.

The bears may be gone, but their old cages can still be found.

The site of Paul Revere's historic two lantern warning.

The first mosque in the world to receive electricity.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Berlin's old airport.

What started as a tongue-in-cheek shrine is now a full-blown museum celebrating "The Hoff" and his longtime love affair with Berlin.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

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

A slice of central Asia in the middle of Berlin.

The most visited, and possibly most controversial, museum in Germany.

When a supermarket opened up shop within a medieval building it became protected by UNESCO on a technicality.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

This massive subterranean fissure is known as the "underground Grand Canyon."