This picturesque Umbrian city has a subterranean side that has long remained hidden.

A hidden "place of interment for gentlemen."

Visit the monolithic tomb of America's most famous general.

The 28-foot granite map plots the locations of 40 theaters in New York City.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Commemorating the spot where the famous scientist fed his pigeons.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

This subterranean oyster house has been the pearl of Grand Central Station since 1913.

The famous facade of Grand Central Terminal hides a regulation tennis court—and it's not the first one.

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

Manhattan's lighthouse, erected at the insistence of the unsinkable Molly Brown.

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

In its day this historic fort held 100 cannons pointed in almost every direction to protect New York.

Lie in a hammock where George Washington stood.

A town trapped in time - 1958 to be exact.

Once America's longest-manned military fort, now an abandoned hulk.

World Trade Center memorial likened to a woman's sexual organ.

Lady Liberty's first beacon of enlightenment is now displayed in a museum near the statue.

This simple Manhattan salt house is artfully shaped... well, like a giant granule of salt.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

Adherence to strict Jewish laws is required to enter this ultra-conservative New York village.

Series of storm drains connected to a dark urban legend.

These mystical miniature houses bring a touch of magic to the New Jersey woods.