This 19th-century Hamptons windmill was once home to modernist painter Agnes Pelton.

These expertly crafted, scientifically accurate glass sea creatures were once an international phenomenon.

All that remains of the once-booming chain is a single orange-roofed restaurant.

Need to book a room at the Hotel Pennsylvania? Just dial up 6-5000.

An abandoned horticulture institute gloomily presides over rows of derelict and vine-wrought greenhouses.

Beneath the mossy overgrowth covering this once-sprawling campus lies decades of history and the secrets that come with it.

This former theme park in New York's Adirondack Mountains fell into ruin before being resurrected as a state-run campground

Tucked in the back of this amazing antique store is an important piece of medical history.

The oldest working cattle ranch in the U.S.

A building made mostly of cast iron features a 1:45 scale lego model of its self.

Starting in 1961, Brookhaven National Labs regularly irradiated a section of forest with a canister of Cesium-137 to study the effects of hard gamma radiation on an ecosystem.

This 1850s mansion reveals how rich Americans lived in the Victorian era.

Beneath its placid surface, one of New York City's primary sources of drinking water hides a haunted past.

This installation turns abstract economics into a stark, public spectacle.

Time travel back to the 19th century and catch an old-timey baseball game at a 209-acre recreated village.

A rare forest habitat nestled behind two sand dunes.

Wooden pavers represent a 17th-century barrier that gave Wall Street its name.

Perhaps the most storied New York City eatery, Delmonico’s reshaped American restaurants.

It's common to find the famous science communicator's grave adorned with pale blue marbles.

This formerly abandoned amusement park includes a classic carousel and a replica of Mark Twain's famous hut-like Elmira study.

This century-old independent movie theater with an iconic Art Deco neon sign survived a devastating fire in 2016.

A unique work of art that was created without permission.

A plaque on a rock dedicated to a famous, forgotten author, and put in an impossible place.

Once the site of seances, this restaurant is said to be haunted by several ghosts.