This mysterious marker puzzles pedestrians and infuriates geographers.

The first "Hall of Fame" in America was designed by legendary Gilded Age architect Stanford White for what was then the NYU uptown campus.

Hidden inside one of the world's most well-visited zoos is a secret plaque promising eternal life.

The home, museum, and death site of Kodak's influential founder.

A New York warehouse filled with an enormous amount of goods saved from the landfills and donated for creative use.

The gravestone of the suffragist leader attracted extra visitors during the 2016 election.

One of many reminders of Tesla's scientific contributions overlooks the falls which inspired him.

Brooklyn's most iconic restaurant, resurrected.

A collection of the best toys ever made inside a museum devoted to play.

This abandoned cemetery is crumbling into ruin, exposing the artifacts and bodies buried there.

The world’s largest collection of Tiffany glass sits in a warehouse in Queens.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

A peaceful international sculpture garden in upstate New York.

The remains of what was once the world's steepest passenger funicular.

The birthplace of America's favorite fruit-flavored mystery dessert.

An old dining hall now serves up ghost stories for lusty locals.

This once-grand marvel of engineering is now 41 miles of scenic hiking trail.

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

"A hideous albatross in the Hudson River Valley."

One of Frank Lloyd Wright's greatest—and favorite—architectural masterpieces was almost lost.

This locally-famous crevasse in New York State is icy all year round.

This secluded ruin was once a home for exotic plants.

Eclectic architecture in the woods of New York.

This once sprawling resort now sits abandoned, filled with graffiti and vibrant colors from an era long passed.