The oldest colonial fortress in the Americas was once the home and later prison of Christopher Columbus.

Built in 1512, the oldest cathedral in the Americas.

This giant subway sculpture celebrates the fruit that inspired the theory of gravity.

Stockholm's narrowest alley is barely over two feet wide.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

The painter who popularized "bulls" and "bears" as symbols for the stock market didn't get a proper headstone for over a century.

Church featuring "high Victorian gothic" architecture.

A mass grave for victims of one of the city’s worst fires.

Final resting place of the immigrant who brought artificial seltzer water to America.

A hidden architectural treasure in New York's Brooklyn.

A way to take your secrets to someone else's grave.

This outdoor gallery of graffiti-covered walls pays homage to the past, present, and possible future of street art.

A Victorian cemetery in the heart of Brooklyn remains a popular mecca of morbid curiosity.

This interactive gallery makes you feel like you've stepped into a fantasy world filled with whimsical monsters.

The factory for the popular Dumbo location, the Greenpoint shop is a quiet gem.

Detailed facade of a brownstone in Boerum Hill.

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

Tucked in a nondescript downtown Brooklyn mall is a bar containing a remarkable turn of the century anatomical wax collection last seen in 1920s Berlin.

A very classy 1920s-era bar right in Grand Central Station.

New York City's smallest piece of private property.

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

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