America's greatest forgotten garden and the former stomping grounds of Son of Sam.

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

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

This dilapidated castle-like structure overlooks the Hudson River at one of its widest points and was once home to nuns.

The ruins of an abandoned 18th-century town that is slowly being reclaimed by the forest.

These World War I shooting range tunnels are now haunted halls of underground graffiti accessed through the roots of a tree.

An Escher-inspired library dedicated to the wonders of the human mind, yet closed to the public.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

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

A museum designed by and dedicated to P.T. Barnum in the town where he is buried.

While many places make the claim, the Library of Congress says this restaurant is the birthplace of the hamburger.

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

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

This sprawling woodland estate was the brainchild of iconic American industrial designer Russel Wright.

The largest known open fault in the United States is basically a giant natural refrigerator.

A religious-themed park filled with folk art to bring biblical stories to life that fell into disrepair and now being restored.

A castle inspired by medieval architecture is hidden in the woods of Connecticut.

A ruined mansion hidden in the woods of the Hudson Valley, home of a tragically doomed romance.

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

This abandoned factory on the Hudson River once churned out a million bricks a week.

A miniature village lies nearly forgotten in the forest by the side of a major highway.

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

This mouldering abandoned mental hospital was once a center for progressive healing.

For over 80 years, Mayan ruins stood proudly in a most unlikely location.