Read between the lines of the subway map to find the hidden abandoned Civil War fort.

The highest point in New Jersey is marked by a massive, if simply named, obelisk.

Memorial built in 1922 in remembrance of WWI casualties.

Tucked behind New Jersey's abandoned Gingerbread Castle lie the eerie ruins of a once-flourishing paper mill.

Step inside Lucy, the world's largest "elephant."

This disastrous New Jersey safari park saw animal attacks, escapes, and disease before being abandoned.

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

This tiny New Jersey village has lived many lives but seems determined to remain a ghost town.

This historic iron-working village is now a ghost town so immaculate that it looks as though it was recently built.

The end of the 4 Line is also the end of the line for 300,000 souls in one of NYC's most illustrious cemeteries.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A crumbling hospital from the 1850s on Roosevelt Island.

The first "Hall of Fame" in America was designed by legendary Gilded Age architect Stanford White for what was then the NYU uptown campus.

The heroic sled dog of the 1925 serum run is preserved in taxidermy.

First a horse rendering plant, then a 19th century landfill, this beach is full of glass from thousands upon thousands of broken bottles.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

Besieged by war, this castle ruin has crumbled into a peaceful picnic spot.

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

A 100-year-old purveyor of curiosities, curios, and kitsch featuring mummies, shrunken heads, and a Fiji Mermaid.

This immaculate and historic water garden culminates in a massive stone dining table with an inset fountain for chilling the wine of the Cardinal's guests.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

An enormous dragon scales the walls of this 17-story temple.

A theme park attraction designed to turn your children into LARPers.