A small peaceful park and waterfall tucked amid the urban grind of Midtown Manhattan.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

World's first "penitentiary," meant to be humane, drove men insane.

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

Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

A restaurant and observation deck built in a unique broadcasting antenna.

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

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

One of Ireland's most infamous prisons for rebels including men, women and children.

Leaf through over 30,000 artists' sketchbooks in what may be the world's largest collection of doodles

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

This public baseball field is a beloved remainder from of one of the most historic stadiums in the country.

Controversial tribute to the heavyweight champion boxer who grew up in Detroit.

Over a thousand feet beneath the Detroit streets is a subterranean metropolis few are allowed to enter.

The world’s largest Masonic temple was saved by the White Stripes.

The concrete shell of an industry giant remains as a playground for graffiti artists, auto scrappers, and paintball warriors.

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.

These enduring murals depicting a distinctly Marxist tribute to capitalism could not even be defeated by McCarthyism.

One man's attempt to create an artistic wonder on a run-down block in Detroit.

A Beaux-Arts triumph set to become Ford's innovation campus