This sandstone gorge in New York State's Adirondack Mountains is home to waterfalls, flumes, and more.

A feminist who put a pretty face on suffrage when she rode a horse through the Capitol.

A perfect replica of the beloved show's first set.

Naturally formed white marble arch housed in an abandoned marble quarry from the 1800s.

An Adirondacks museum housed in the former studio of Marcella Sembrich, the 19th century opera star most famous for her role of Mimi in "La Boheme."

An unassuming island in the middle of the Hudson that hosts campers, including Aleister Crowley.

An abandoned asylum where patients have been forgotten but their possessions remain.

Now the final resting place of prominent artists and musicians, it was originally founded to separate the rich from the poor in death.

This huge, disused viaduct is now a crumbling concrete underworld of covered in years of graffiti.

Historic town settled in the 19th century because of its convenient location along a popular coal transport route.

This hospital fell into ruins after failing to act as the advocate for the mentally ill it was designed to be.

A historic grist mill and active sluice on the Black River.

A recently abandoned psych ward at the end of Sanatorium Road.

American involvement in World War I officially ended in 1921 in New Jersey, three years late and thousands of miles from the battlefield.

A playground inspired by differential calculus dangles from the ceiling of the Liberty Science Center.

These mystical miniature houses bring a touch of magic to the New Jersey woods.

The "Skinny House" is made from scrap, salvage, and a neighbor’s kindness.

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

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

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

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

Haunted Victorian house that inspired a legendary "Ghostbusters" court ruling.

Protecting the future of some of the rarest and most misunderstood mammals of North America.

Home of Philip Johnson, one of the 20th century's most influential architects.