Copenhagen's "other" little mermaid marks the historic location of past sea maid sightings.

Copenhagen's celebrated theme park and gardens.

This ordinary street was made infamous by a legendary visit from the devil.

Historic funicular railway, believed to be the shortest railroad in the world.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

Once a ferry dock, radio transmitter, and now a new Greenpoint park.

Known as the "Forgotten City" it was home to industry, riots, artists, squatters, and to one of the largest single disaster fires in New York City.

A terrific purveyor of natural history objects and curios.

This hidden oasis features a stunning view of the Hudson River and the Palisades from a castle-like museum.

Mysterious 500-year-old tapestries depict a unicorn hunt.

The only home that Alexander Hamilton ever owned has a history almost as troubled as his own.

A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.

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

A crumbling hospital from the 1850s on Roosevelt Island.

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

The first piece of public art dedicated to LGBT rights.

Elevated freight railway turned wildly successful urban park.

A dilapidated dock tells the story of Titanic’s missed arrival.

Try not to get slimed in Tribeca.

Amid skyscrapers and traffic exists this unique aquatic ecosystem.

An uber-secure, windowless tower of doom in the center of Manhattan is an NSA spyscraper.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.