One man's swirling six-acre monument of stone.

The oldest continuously inhabited street in America.

Neon signs that grace the windows of Bergdorf Goodman's and Tiffany & Co. come from this studio in Brooklyn.

An abandoned castle owned and ignored by Masons carries a cursed history.

This small Catskills village has six independent bookstores and more bookshops than restaurants.

This local landmark is home to art galleries and the area's only community darkroom.

This Art Deco fortress in upstate New York gives Manhattan's vaunted examples of the style a run for their money.

Possibly the smallest church in the world floats in the middle of a pond.

A historic recreation of the golden age of the Erie Canal, abandoned for some time, slowly being restored.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

This abandoned ironworks was once the most important military supplier in America.

The first pet cemetery in the United States.

One of the earliest bowling lanes in the U.S. doubled as a sewing school during a time when women had little job opportunity.

Reclaimed by nature, the ruins of Doodletown, New York are remnants of a town consumed by a state park.

Astonishing collection of helmets, scientific instruments, and medical models.

The home of one of America's most wealthy industrialists is now a historic site that remembers a more decadent time in the country's history.

The real-life site of Ichabod Crane's infamous gourd attack.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

This tiny church near Sleepy Hollow contains Henri Matisse's last work, a rose window, and nine windows by Marc Chagall.

This giant rock arrived at this quiet park thousands of years ago on the back of a massive glacier.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

Oldest surviving example of a Dutch saltbox frame house in America.

A Collegiate Gothic quadrangle that surrounds an 18th century secondary school whose financing came from the likes of Alexander Hamilton and Aaron Burr, among others.