This plot of old-growth forest is the largest surviving remnant of New York City's original woodland.

Along the Palisades skyline are the ruins of a large mansion built in 1911 and demolished in the 1930s.

This derelict building used to house infirm Freemasons, their widows, and orphans.

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

Panoramic views of the city of New Haven and the Long Island Sound, with a side of history.

This "thrice-cursed" island is allegedly home to Captain Kidd's lost treasure.

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

This isolated community does not want you to visit.

Glacial erratic or man-made dolmen? It probably wasn't druids.

This abandoned psychiatric hospital once housed more than 4,000 patients in the middle of a quaint New England town.

The largest Buddha statue in the Western Hemisphere is just 50 miles north of NYC.

The attic and basement house two museums stuffed with oddities like swallowed spoon handles and a shrunken head.

Final resting place of Typhoid Mary.

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

A formerly abandoned mental institute, now back in business.

A monument stands to the famous suffragist who penned the declaration for women's equal rights, including the right to vote.

A former connection to City Island, it has been abandoned since the 1930s.

The loneliest island in New York.

An abandoned Gold Coast-era mansion once intended for the exiled ruler of Albania, who never arrived.

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

Spies, love letters, and ghost stories have all left their mark on this home-cum-museum.

This forgotten graveyard in rural New York State once served a pioneering hospital.

A lone tower rises above the cliffs in a city park, offering fantastic views of the Connecticut landscape.

A millionaire's abandoned swimming pool from the gilded age of one of America's most distinguished families.