This recipe is set in stone.

The painter who popularized "bulls" and "bears" as symbols for the stock market didn't get a proper headstone for over a century.

A mass grave for victims of one of the city’s worst fires.

A Victorian cemetery in the heart of Brooklyn remains a popular mecca of morbid curiosity.

The home of aviation trailblazers, in a remote corner of the big city.

This abandoned seaside fortress is now simply an imposing ruin being taken back by nature.

Final resting place of Typhoid Mary.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

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

This outpost of America's most popular fast-food restaurant is housed inside a palatial mansion.

The abandoned grounds and derelict greenhouses of this once-magnificent Edwardian estate are now a nature preserve open for exploration.

The site of a tragic massacre that spawned a multimedia franchise.

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

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

A formerly abandoned mental institute, now back in business.

Beneath the mossy overgrowth covering this once-sprawling campus lies decades of history and the secrets that come with it.

An unrealized dream to wirelessly electrify the entire Earth.

An eccentric playboy's astounding natural history collection.

A mysterious air force base built to resemble a Long Island fishing village.