The Victorian-era greenhouse is stuffed with tropical plants, and open 365 days a year.

A botanically themed auditorium blooms within the world’s last operating double-decker theater.

The Ryerss mansion in Burholme Park now houses a community library and a museum filled with a trove of oddities from around the world.

Huge masonic hall in Philadelphia with lavishly themed rooms.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

Where America's first doomsday cult awaited the end of the world.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

World's first "penitentiary," meant to be humane, drove men insane.

Sip a cappuccino in the historic cafe that introduced them to the United States.

Built in the 1920s, this co-op in the Bronx feels more like an Italian villa than a typical New York apartment building.

This 19th century brick building in Brooklyn stands out like the anachronistic landmark that it is.

The one-time epicenter of American songwriting is now a little remembered Manhattan commercial block.

You must take the A train... to the last active cemetery in Manhattan.

The Vatican of the movie industry turned into an actual church.

A posh members-only club with a literally dramatic history.

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

This secluded ruin was once a home for exotic plants.

One of the oldest Jewish cemeteries in the city, it is now overgrown with an urban forest.

Once America's longest-manned military fort, now an abandoned hulk.

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.

A collection of fanzines, recordings, and documents detailing the rise and influence of the feminist punk movement.

An oasis of calm amid the chaos of the boardwalk, the museum traces the heritage of this beloved beachside amusement park.

Long the exclusive domain of birds and vagabonds, this little-known Central Park peninsula is open to the public once more.