This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

Some call this eerie forest of crooked trees the "Bermuda Triangle of Romania."

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A crumbling hospital from the 1850s on Roosevelt Island.

What was once one of the country's largest confectionary plants is now an abandoned ruin, but is still pretty sweet.

A century-old network of freight tunnels underneath the city's historic business district.

These abandoned grain silos and tunnels are an urban exploration dream.

A hollow cement depiction of time's inexorable effect on the human body.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Final resting place for the Triangle Shirtwaist fire’s unidentified victims.

A little lighthouse in New York City, surrounded by mysterious stories of insanity-driven construction.

Nondescript elevator doors open to reveal a stunning, surreal world.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

Tucked in a nondescript downtown Brooklyn mall is a bar containing a remarkable turn of the century anatomical wax collection last seen in 1920s Berlin.

The "Seinfeld" diner.

A semi-scholarly approach to sex.

This Buddhist temple is home to the graves of the Japanese national legends, the 47 Ronin.

The fairy tale castle of the "fairy-tale king."

An incredible menagerie of more than 3 million taxidermied animals at the oldest science museum in Europe.

The middle finger of modernity.

Every color in the rainbow awaits.

Museum celebrating the achievements of the Soviet space program.

Dr. Strangelove-esque tours reveal the inside a bunker once reserved for Stalin himself.

One part local history, 99 parts gruesome haunted house.